input
stringlengths
20
127k
target
stringlengths
20
119k
problem_id
stringlengths
6
6
import sys sys.setrecursionlimit(10 ** 5 + 10) def input(): return sys.stdin.readline().strip() def resolve(): n=int(eval(input())) cnt=0 while True: cnt+=1 if n<=1000*cnt: print((1000*cnt-n)) break resolve()
import sys sys.setrecursionlimit(10 ** 5 + 10) def input(): return sys.stdin.readline().strip() def resolve(): n=int(eval(input())) print((0 if n%1000==0 else 1000-(n%1000))) resolve()
p02612
import sys n = int((eval(input()))) if n%1000 == 0: print((0)) else: while n > 1000: n -= 1000 print((1000-n))
import sys n = int((eval(input()))) if n%1000 == 0: print((0)) else: for i in range(10): if n < 1000: print((1000-n)) sys.exit() else: n -= 1000
p02612
(r, c) = [int(i) for i in input().split()] ct = [0 for d in range(c)] tmp = [] for rc in range(r): tmp = [int(i) for i in input().split()] total = 0 for cc in range(c): ct[cc] += tmp[cc] total += tmp[cc] print(tmp[cc], end=' ') print(total) total = sum(ct) print(' '.join([str(i) for i in ct]), total)
(r, c) = [int(i) for i in input().split()] table = [] for rc in range(r): table.append([int(i) for i in input().split()]) table.append([0 for _ in range(c + 1)]) for rc in range(r): row_total = 0 for cc in range(c): table[r][cc] += table[rc][cc] row_total += table[rc][cc] table[rc].append(row_total) table[r][c] += row_total for row in table: print((' '.join([str(column) for column in row])))
p02413
(r, c) = [int(i) for i in input().split()] ct = [0 for d in range(c)] tmp = [] for rc in range(r): tmp = [int(i) for i in input().split()] total = 0 for cc in range(c): ct[cc] += tmp[cc] total += tmp[cc] print(tmp[cc], end=' ') print(total) total = sum(ct) print(' '.join([str(i) for i in ct]), total)
(r, c) = [int(i) for i in input().split()] last_row = [0 for _ in range(c+1)] for _ in range(r): row = [int(i) for i in input().split()] for cc in range(c): last_row[cc] += int(row[cc]) print(row[cc], end=' ') print(sum(row)) last_row[-1] = sum(last_row) print(' '.join([str(a) for a in last_row]))
p02413
r, c = list(map(int, input().split(' '))) matrix = [] total_cols = [0 for i in range(c+1)] for i in range(r): rows = list(map(int, input().split(' '))); total = sum(rows) rows.append(total) total_cols = [ total_cols[i] + x for i, x in enumerate(rows) ] matrix.append(rows) matrix.append(total_cols) for row in matrix: print((' '.join([str(i) for i in row])))
def main(): r, c = [int(x) for x in input().split()] matrix = [] totals = [0 for _ in range(c+1)] for _ in range(r): nums = [int(x) for x in input().split()] total = sum(nums) row = nums + [total] matrix.append(row) for i in range(c+1): totals[i] += row[i] matrix.append(totals) for m in matrix: print((" ".join([str(x) for x in m]))) if __name__ == '__main__': main()
p02413
(r,c) = [int(i) for i in input().split()] table = [] for rc in range(r): table.append([int(i) for i in input().split()]) table.append([0 for _ in range(c + 1)]) for rc in range(r): row_total = 0 for cc in range(c): table[r][cc] += table[rc][cc] row_total += table[rc][cc] table[rc].append(row_total) table[r][c] += row_total for row in table: print((' '.join([str(column) for column in row])))
(r, c) = [int(i) for i in input().split()] last_row = [0 for _ in range(c+1)] for _ in range(r): row = [int(i) for i in input().split()] for cc in range(c): last_row[cc] += int(row[cc]) print(row[cc], end=' ') print(sum(row)) last_row[-1] = sum(last_row) print(' '.join([str(a) for a in last_row]))
p02413
h, w = [int(i) for i in input().split()] date = [[int(q) for q in input().split()] for e in range(h)] date2=[] date3=[] for r in range(0, h): for t in range(0, w): print(date[r][t], end=' ') print(sum(date[r])) for k in range(0,w): for j in range(0,h): date2.append(date[j][k]) for n in range(0,w*h,h): print(sum(date2[n:(n+h)]),end=' ') for m in range(h): date3.append(sum(date[m])) print(sum(date3))
r, c =[int(i) for i in input().split()] date =[] sum_row = [0] * (c + 1) for ri in range(r): date.append([int(i) for i in input().split()]) date[ri].append(sum(date[ri])) print((" ".join([str(d) for d in date[ri]]))) for ci in range(c + 1): sum_row[ci] += date[ri][ci] print((" ".join([str(s) for s in sum_row])))
p02413
r, c = map(int, input().split()) a = [[0 for i in range(c+1)] for j in range(r+1)] for i in range(r): l = list(map(int, input().split())) for j in range(c): a[i][j] = l[j] a[i][c] += a[i][j] for i in range(c+1): for j in range(r): a[r][i] += a[j][i] for i in range(r+1): for j in range(c+1): if j == c: print(str(a[i][j])) else: print(str(a[i][j]) + " ", end="")
r, c = map(int, input().split()) a = [[int(i) for i in input().split()] for j in range(r)] b = [[0 for i in range(c+1)] for j in range(r+1)] for i in range(r): for j in range(c): b[i][j] = a[i][j] b[i][c] += a[i][j] for i in range(c+1): for j in range(r): b[r][i] += b[j][i] for i in range(r+1): for j in range(c+1): if j == c: print(b[i][j]) else: print("{0} ".format(b[i][j]), end = "")
p02413
r,c=map(int,input().split()) a,b=[],[0]*c for i in range(r): x=list(map(int,input().split())) print(*x, end=' ') print(sum(x)) for j in range(c): b[j]+=x[j] print(*b, end=' ') print(sum(b))
r,c=map(int,input().split()) a=[0]*c for i in range(r): x=list(map(int,input().split())) for j in range(c): a[j]+=x[j] print(*x, end=' ') print(sum(x)) print(*a, end=' ') print(sum(a))
p02413
m,n=map(int,input().split()) a =[] for _ in range(m): a.append(list(map(int,input().split()))) for index in range(m): a[index].append(sum(a[index])) for a_column in a: for num in a_column[:-1]: print(num, end=' ') print(a_column[-1]) for row_index in range(n): sum = 0 for a_column in a: sum += a_column[row_index] print(sum, end=' ') sum = 0 for a_column in a: sum += a_column[-1] print(sum)
m,n=list(map(int,input().split())) a =[] for _ in range(m): a.append(list(map(int,input().split()))) for index in range(m): a[index].append(sum(a[index])) for a_column in a: print((' '.join(map(str, a_column)))) a.append([0]*(n+1)) for row_index in range(n+1): for a_column in a[:-1]: a[-1][row_index] += a_column[row_index] print((' '.join(map(str, a[-1]))))
p02413
N,M = list(map(int,input().split())) table = [1,1] while len(table) <= N: temp = table[0] for i in range(len(table)-1): table[i+1] += temp temp = table[i+1]- temp table[i+1] %= M table.append(1) S = [1] rev2 = pow(2, M-2, M) base = pow(2, N, M) ans = 0 S = [1] for K in range(N+1): res = table[K] % M res = (res * pow(2, pow(2, N - K, M-1), M)) % M b = 1 v = 0 T = [0]*(K+2) for L in range(K): T[L+1] = s = (S[L] + (L+1)*S[L+1]) % M v += s * b b = (b * base) % M v += b T[K+1] = 1 S = T res = (res * v) % M if K % 2: ans -= res else: ans += res ans %= M base = (base * rev2) % M print(ans)
N, M = list(map(int, input().split())) fact = [1]*(N+1) rfact = [1]*(N+1) for i in range(1, N+1): fact[i] = r = (i * fact[i-1]) % M rfact[i] = pow(r, M-2, M) S = [1] rev2 = pow(2, M-2, M) base = pow(2, N, M) ans = 0 S = [1] for K in range(N+1): res = (fact[N] * rfact[K] * rfact[N-K]) % M res = (res * pow(2, pow(2, N - K, M-1), M)) % M b = 1 v = 0 T = [0]*(K+2) for L in range(K): T[L+1] = s = (S[L] + (L+1)*S[L+1]) % M v += s * b b = (b * base) % M v += b T[K+1] = 1 S = T res = (res * v) % M if K % 2: ans -= res else: ans += res ans %= M base = (base * rev2) % M print(ans)
p03375
while True: n = int(eval(input())) if n == 0: break wlst = list(map(int, input().split())) dp = [[0] * n for _ in range(n + 1)] def check(left1, right1, left2, right2, cnt): if left1 > right1 and left2 > right2: return cnt if left1 > right1:return dp[right2 - left2 + 1][left2] + cnt if left2 > right2:return dp[right1 - left1 + 1][left1] + cnt ret = cnt + dp[right1 - left1 + 1][left1] + dp[right2 - left2 + 1][left2] if abs(wlst[right1] - wlst[left2]) <= 1: ret = max(ret, check(left1, right1 - 1, left2 + 1, right2, cnt + 1)) if right1 - left1 + 1 >= 2 and dp[2][right1 - 1]: ret = max(ret, check(left1, right1 - 2, left2, right2, cnt + 1)) if right2 - left2 + 1 >= 2 and dp[2][left2]: ret = max(ret, check(left1, right1, left2 + 2, right2, cnt + 1)) return ret for length in range(2, n + 1): for left in range(n - length + 1): for k in range(length - 1): dp[length][left] = max(dp[length][left], check(left, left + k, left + k + 1, left + length - 1, 0)) print((dp[n][0] * 2))
def main(): while True: n = int(eval(input())) if n == 0: break wlst = list(map(int, input().split())) connect = [[None] * n for _ in range(n)] for i in range(n): for j in range(n): connect[i][j] = abs(wlst[i] - wlst[j]) <= 1 max_lst = [[False] * (n + 1) for _ in range(n + 1)] for i in range(n + 1): max_lst[0][i] = True dp = [[0] * n for _ in range(n + 1)] def check(length, left): ret = dp[length - 1][left] for k in range(length - 1, 0, -2): if not max_lst[length - k - 1][left + k]:continue if connect[left + k - 1][left + length - 1]: temp = length - k + 1 + dp[k - 1][left] if ret < temp: ret = temp return ret for length in range(2, n + 1): for left in range(n - length + 1): dp[length][left] = check(length, left) if dp[length][left] == length: max_lst[length][left] = True print((dp[n][0])) main()
p01096
import math,string,itertools,fractions,heapq,collections,re,array,bisect,sys,random,time,copy,functools sys.setrecursionlimit(10**7) inf = 10**20 eps = 1.0 / 10**10 mod = 10**9+7 dd = [(-1,0),(0,1),(1,0),(0,-1)] ddn = [(-1,0),(-1,1),(0,1),(1,1),(1,0),(1,-1),(0,-1),(-1,-1)] def LI(): return [int(x) for x in sys.stdin.readline().split()] def LI_(): return [int(x)-1 for x in sys.stdin.readline().split()] def LF(): return [float(x) for x in sys.stdin.readline().split()] def LS(): return sys.stdin.readline().split() def I(): return int(sys.stdin.readline()) def F(): return float(sys.stdin.readline()) def S(): return input() def pf(s): return print(s, flush=True) def main(): rr = [] def f(n): a = LI() m = {} def _f(a): l = len(a) if l < 2: return 0 k = tuple(a) if k in m: return m[k] r = 0 for i in range(len(a)-1): if abs(a[i]-a[i+1]) >= 2: continue t = _f(a[:i] + a[i+2:]) + 2 if r < t: r = t m[k] = r return r return _f(a) while True: n = I() if n == 0: break rr.append(f(n)) return '\n'.join(map(str, rr)) print(main())
import math,string,itertools,fractions,heapq,collections,re,array,bisect,sys,random,time,copy,functools sys.setrecursionlimit(10**7) inf = 10**20 eps = 1.0 / 10**10 mod = 10**9+7 dd = [(-1,0),(0,1),(1,0),(0,-1)] ddn = [(-1,0),(-1,1),(0,1),(1,1),(1,0),(1,-1),(0,-1),(-1,-1)] def LI(): return [int(x) for x in sys.stdin.readline().split()] def LI_(): return [int(x)-1 for x in sys.stdin.readline().split()] def LF(): return [float(x) for x in sys.stdin.readline().split()] def LS(): return sys.stdin.readline().split() def I(): return int(sys.stdin.readline()) def F(): return float(sys.stdin.readline()) def S(): return input() def pf(s): return print(s, flush=True) def main(): rr = [] def f(n): a = LI() l = len(a) s = set() r = 0 for i in range(l-1): if abs(a[i] - a[i+1]) < 2: s.add((i,i+1)) for i in range(4, l+1): for j in range(l-i+1): k = j + i - 1 if (j+1, k-1) in s and abs(a[j] - a[k]) < 2: s.add((j,k)) continue for m in range(j+2,k,2): if (j,m-1) in s and (m,k) in s: s.add((j,k)) break m = {} m[l] = 0 def _f(i): if i in m: return m[i] r = 0 for j in range(i,l+1): t = _f(j+1) if (i,j) in s: t += j - i + 1 if r < t: r = t m[i] = r return r return _f(0) while True: n = I() if n == 0: break rr.append(f(n)) return '\n'.join(map(str, rr)) print(main())
p01096
def cmb(n,r,mod): if r<0 or r>n: return 0 r=min(r,n-r) return g1[n]*g2[r]*g2[n-r]%mod n,k=list(map(int,input().split())) a=list(map(int,input().split())) l=[] l2=[] for i in range(n): l.append([a[i],i]) l.sort() for i in range(n): l2.append([l[i][1],i]) l2.sort() mod=10**9+7 g1=[1,1] g2=[1,1] inverse=[0,1] for i in range(2,n+1): g1.append((g1[-1]*i)%mod) inverse.append((-inverse[mod%i]*(mod//i))%mod) g2.append((g2[-1]*inverse[-1])%mod) ans=0 for i in range(n): ans+=a[i]*cmb(l2[i][1],k-1,mod) ans%=mod for i in range(n): ans-=a[i]*cmb(n-l2[i][1]-1,k-1,mod) ans+=mod ans%=mod print(ans)
def cmb(n,r,mod): if r<0 or r>n: return 0 r=min(r,n-r) return g1[n]*g2[r]*g2[n-r]%mod n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort() mod=10**9+7 g1=[1,1] g2=[1,1] inverse=[0,1] for i in range(2,n+1): g1.append((g1[-1]*i)%mod) inverse.append((-inverse[mod%i]*(mod//i))%mod) g2.append((g2[-1]*inverse[-1])%mod) ans=0 for i in range(n): ans+=a[i]*cmb(i,k-1,mod) ans%=mod for i in range(n): ans-=a[i]*cmb(n-i-1,k-1,mod) ans+=mod ans%=mod print(ans)
p02804
#!/usr/bin/env python3 import sys MOD = 1000000007 # type: int from itertools import accumulate def mod_factorial(n): value = 1 for i in range(n,0,-1): value*=i value%=MOD return value def solve(N: int, K: int, A: "List[int]"): A.sort() n = N-1 r = K-1 # nCkTable[i] = iCr nCkTable = [0]*(n+1) start = 1 for _ in range(r): start *= n start %= MOD n -= 1 bunbo = mod_factorial(r) bunbo_gyakugen = pow(bunbo,MOD-2,MOD) n = N-1 for i in range(n, r-1, -1): nCkTable[i] = start*bunbo_gyakugen%MOD start*=pow(i,MOD-2,MOD) start*=i-r answer = 0 for i in range(N): answer += A[i]*(nCkTable[i]-nCkTable[N-1-i]) answer%=MOD print((answer%MOD)) return def main(): def iterate_tokens(): for line in sys.stdin: for word in line.split(): yield word tokens = iterate_tokens() N = int(next(tokens)) # type: int K = int(next(tokens)) # type: int A = [int(next(tokens)) for _ in range(N)] # type: "List[int]" solve(N, K, A) if __name__ == '__main__': main()
#!/usr/bin/env python3 import sys MOD = 1000000007 # type: int from itertools import accumulate def mod_factorial(n): value = 1 for i in range(n,0,-1): value*=i value%=MOD return value def solve(N: int, K: int, A: "List[int]"): A.sort() n = N-1 r = K-1 # nCkTable[i] = iCr nCkTable = [0]*(n+1) start = 1 for _ in range(r): start *= n start %= MOD n -= 1 bunbo = mod_factorial(r) bunbo_gyakugen = pow(bunbo,MOD-2,MOD) n = N-1 for i in range(n, r-1, -1): nCkTable[i] = start*bunbo_gyakugen%MOD start*=pow(i,MOD-2,MOD) start*=i-r start%=MOD answer = 0 for i in range(N): answer += A[i]*(nCkTable[i]-nCkTable[N-1-i]) answer%=MOD print((answer%MOD)) return def main(): def iterate_tokens(): for line in sys.stdin: for word in line.split(): yield word tokens = iterate_tokens() N = int(next(tokens)) # type: int K = int(next(tokens)) # type: int A = [int(next(tokens)) for _ in range(N)] # type: "List[int]" solve(N, K, A) if __name__ == '__main__': main()
p02804
N, K = list(map(int, input().split())) A = list(map(int, input().split())) A = sorted(A) def framod(n, mod, a=1): for i in range(1,n+1): a=a * i % mod return a def power(n, r, mod): if r == 0: return 1 if r%2 == 0: return power(n*n % mod, r//2, mod) % mod if r%2 == 1: return n * power(n, r-1, mod) % mod def comb(n, k, mod): a=framod(n, mod) b=framod(k, mod) c=framod(n-k, mod) return (a * power(b, mod-2, mod) * power(c, mod-2, mod)) % mod p = 1000000007 ans = 0 for i in range(N- K +1): ans += ((A[N-1-i] - A[i])*comb(N-1-i, K-1, p)) ans = ans % p print(ans)
N, K = list(map(int, input().split())) A = list(map(int, input().split())) A = sorted(A) p = 1000000007 frac = [1] for i in range(N): frac.append(frac[i]*(i+1)%p) def power(n, r, mod): if r == 0: return 1 if r%2 == 0: return power(n*n % mod, r//2, mod) % mod if r%2 == 1: return n * power(n, r-1, mod) % mod def comb(n, k, mod): a=frac[n] b=frac[k] c=frac[n-k] return (a * power(b, mod-2, mod) * power(c, mod-2, mod)) % mod ans = 0 for i in range(N- K +1): ans += ((A[N-1-i] - A[i])*comb(N-1-i, K-1, p)) ans = ans % p print(ans)
p02804
def nCr(n,r): if n < 0 or r < 0 or n < r: return 0 if n - r < r: r = n - r if r == 0: return 1 if r == 1: return n # 分子のn*(n-1)*...がr個分続くやつ numerator = [n-r+k+1 for k in range(r)] # 分母:r!=r*(r-1)*...*3*2の要素 denominator = [k+1 for k in range(r)] # 分母の要素で割れる部分を割っていく部分 for p in range(2, r+1): # 分母は1,2,3,...rのようになっており、1は意味がないのでスキップした形か pivot = denominator[p-1] if pivot > 1: # 分子のX番目と分母のX-offset番目が共通の約数を持つということだと思う。piv分ずれているのだから、pivの倍数というところか offset = (n-r) % p for k in range(p-1, r, p): # 約分できる要素について割る numerator[k - offset] /= pivot denominator[k] /= pivot ret = 1 for k in range(r): if numerator[k] > 1: ret *= int(numerator[k]) return ret N,K = list(map(int, input().split())) MOD = 10**9+7 A = list(map(int, input().split())) A.sort() if N == 1 or K == 1: print((0)) exit() # A_iがminに選ばれる回数と、maxに選ばれる回数それぞれをわけて考えて足していく ans = 0 for i in range(N): # minになれるのは、iの右からK-1個選べる場合 if N - (i+1) >= K-1: ans -= A[i] * nCr(N - (i+1), K-1) % MOD # maxになれるのは、iの左からK-1個選べる場合 if i >= K-1: ans += A[i] * nCr(i, K-1) % MOD ans %= MOD print(ans)
N,K = list(map(int, input().split())) MOD = 10**9+7 A = list(map(int, input().split())) A.sort() if N == 1 or K == 1: print((0)) exit() def nCr(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) # nCr = n! / (r! * (n-r)!) return fact[n] * factinv[r] * factinv[n-r] % p p = MOD #N = 10 ** 6 # N は必要分だけ用意する fact = [1, 1] # fact[n] = (n! mod p) factinv = [1, 1] # factinv[n] = ((n!)^(-1) mod p) inv = [0, 1] # factinv 計算用 for i in range(2, N + 1): # (a * b * c) % MOD = (a * b % MOD) * c % MOD みたいなやつを利用して、大きな値にならないように一ステップごとにMODをとる fact.append((fact[-1] * i) % p) inv.append((-inv[p % i] * (p // i)) % p) factinv.append((factinv[-1] * inv[-1]) % p) # A_iがminに選ばれる回数と、maxに選ばれる回数それぞれをわけて考えて足していく ans = 0 for i in range(N): # minになれるのは、iの右からK-1個選べる場合 if N - (i+1) >= K-1: ans -= A[i] * nCr(N - (i+1), K-1, MOD) # maxになれるのは、iの左からK-1個選べる場合 if i >= K-1: ans += A[i] * nCr(i, K-1, MOD) ans %= MOD print(ans)
p02804
n,k=list(map(int,input().split())) a=sorted(list(map(int,input().split()))) mod=10**9+7 ans=0 MOD=10**9+7 from operator import mul from functools import reduce def cmb(n,r): r = min(n-r,r) if r == 0: return 1 over = reduce(mul, list(range(n, n - r, -1))) under = reduce(mul, list(range(1,r + 1))) return over // under for i in range(n-k+1): ans-=a[i]*cmb(n-i-1,k-1)%mod ans%=mod a=a[::-1] for i in range(n-k+1): ans+=a[i]*cmb(n-i-1,k-1)%mod ans%=mod print((ans%mod))
n,k=list(map(int,input().split())) a=sorted(list(map(int,input().split()))) mod=10**9+7 ans=0 MOD=10**9+7 factorial = [1] inverse = [1] for i in range(1, n+2): factorial.append(factorial[-1] * i % MOD) inverse.append(pow(factorial[-1], MOD - 2, MOD)) # 組み合わせ計算 def nCr(n, r): if n < r or r < 0: return 0 elif r == 0: return 1 return factorial[n] * inverse[r] * inverse[n - r] % MOD for i in range(n-k+1): ans-=a[i]*nCr(n-i-1,k-1)%mod ans%=mod a=a[::-1] for i in range(n-k+1): ans+=a[i]*nCr(n-i-1,k-1)%mod ans%=mod print((ans%mod))
p02804
# modulo:mod # inverse x^(-1) def inv(x): global mod return pow(x,mod-2,mod) # factorial x! def fact(x): global mod res=1 for i in range(2,x+1): res=res*i%mod return res # combination nCr def combi(n,r): if r<0 or r>n: return 0 else: return fact(n)*inv(fact(r))*inv(fact(n-r))%mod mod=10**9+7 N,K=list(map(int,input().split())) A=[-10**10] # 1-ind A.extend(list(map(int,input().split()))) A.sort() # print(A) ans=0 # min for i in range(1,N-K+2): temp=combi(N-i,K-1)%mod ''' print(i,A[i]) print(N-i,K-1) print('min',temp) ''' ans=(ans-temp*A[i])%mod # max for j in range(K,N+1): temp=combi(j-1,K-1) ''' print(j) print(j-1,K-1) print('max',temp*A[j]) ''' ans=(ans+temp*A[j])%mod print(ans)
# modulo:mod # inverse x^(-1) def inv(x): global mod return pow(x,mod-2,mod) # factorial x! def fact(x): global mod res=1 for i in range(2,x+1): res=res*i%mod return res # combination nCr def combi(n,r): if r<0 or r>n: return 0 else: return fact(n)*inv(fact(r))*inv(fact(n-r))%mod mod=10**9+7 N,K=list(map(int,input().split())) A=[-10**10] # 1-ind A.extend(list(map(int,input().split()))) A.sort() # print(A) ans=0 # min p=1 for i in range(N-K+1,0,-1): # print(i,A[i],p) temp=A[i]*p%mod ans=(ans-temp)%mod # print((N-i+1)*inv(N-K-i+2)) p=p*(N-i+1)*inv(N-K-i+2)%mod # max p=1 for j in range(K,N+1): # print(j,A[j],p) temp=A[j]*p%mod ans=(ans+temp)%mod p=p*j*inv(j-K+1)%mod print(ans)
p02804
import sys input = sys.stdin.readline def inv(x): return pow(x, MOD-2, MOD) def C(n, r): if r>n: return 0 #return fact[n]//fact[r]//fact[n-r] #return fact[n]*inv(fact[r])*inv(fact[n-r]) return fact[n]*inv_table[r]*inv_table[n-r] N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() MOD = 10**9+7 if K==1: print((0)) exit() fact = [1] for i in range(1, N+1): fact.append(fact[-1]*i%MOD) #fact.append(fact[-1]*i) inv_table = [-1]*(N+1) for i in range(N+1): inv_table[i] = inv(fact[i]) ans = 0 c_acc = [0] for i in range(N+1): c_acc.append((c_acc[-1]+C(i, K-2))%MOD) for i in range(N): left = c_acc[i]-c_acc[0] right = c_acc[N-i-1]-c_acc[0] #print(left, right) ans += A[i]*(left-right) ans %= MOD print(ans)
def inv(x): return pow(x, MOD-2, MOD) def C(n, r): if r>n: return 0 return fact[n]*inv_table[r]*inv_table[n-r] N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() ans = 0 MOD = 10**9+7 fact = [1] for i in range(1, N+1): fact.append(fact[-1]*i%MOD) inv_table = [-1]*(N+1) for i in range(N+1): inv_table[i] = inv(fact[i]) for i in range(N): ans += A[i]*(C(i, K-1)-C(N-i-1, K-1)) ans %= MOD print(ans)
p02804
import sys def input(): return sys.stdin.readline().strip() def mapint(): return list(map(int, input().split())) sys.setrecursionlimit(10**9) N, K = mapint() from collections import Counter As = list(mapint()) count = Counter(As) mod = 10**9+7 maxi = 0 cum = 0 pos = {} neg = {} pos[0] = 1 neg[0] = 1 As = sorted(list(set(As))) for i in range(1, 10**5+5): pos[i] = pos[i-1]*i%mod neg[i] = pow(pos[i], mod-2, mod) for a in As: cum += count[a] if cum<K: continue for i in range(1, min(K, count[a])+1): if cum-count[a]-K+i<0: continue maxi += a*pos[count[a]]*neg[i]*neg[count[a]-i]*pos[cum-count[a]]*neg[K-i]*neg[cum-count[a]-K+i] maxi %= mod mini = 0 cum = 0 for a in As[::-1]: cum += count[a] if cum<K: continue for i in range(1, min(K, count[a])+1): if cum-count[a]-K+i<0: continue mini += a*pos[count[a]]*neg[i]*neg[count[a]-i]*pos[cum-count[a]]*neg[K-i]*neg[cum-count[a]-K+i] mini %= mod print(((maxi-mini)%mod))
import sys def input(): return sys.stdin.readline().strip() def mapint(): return list(map(int, input().split())) sys.setrecursionlimit(10**9) N, K = mapint() As = list(mapint()) mod = 10**9+7 As.sort() pos = {} neg = {} pos[0] = 1 neg[0] = 1 for i in range(1, 10**5+3): pos[i] = (pos[i-1]*i)%mod neg[i] = pow(pos[i], mod-2, mod) mini = 0 maxi = 0 for i, a in enumerate(As): if i<=N-K: mini += a*pos[(N-i-1)]*neg[K-1]*neg[N-i-K] mini %= mod if i>=K-1: maxi += a*pos[i]*neg[K-1]*neg[i-K+1] maxi %= mod print(((maxi-mini)%mod))
p02804
n,k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) def framod(n, mod, a=1): for i in range(1,n+1): a=a * i % mod return a def power(n, r, mod): if r == 0: return 1 if r%2 == 0: return power(n*n % mod, r//2, mod) % mod if r%2 == 1: return n * power(n, r-1, mod) % mod def comb(n, k, mod): a=framod(n, mod) b=framod(k, mod) c=framod(n-k, mod) return (a * power(b, mod-2, mod) * power(c, mod-2, mod)) % mod ans=0 mod = 10**9+7 a=a[::-1] for i in range(n-k+1): ans += (a[i] * comb(n-i-1, k-1, mod))%mod a=a[::-1] for i in range(n-k+1): ans -= (a[i] * comb(n-i-1, k-1, mod))%mod print((ans%mod))
n,k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) ans=0 mod = 10**9+7 factorial = [1] inverse = [1] for i in range(1, n+2): factorial.append(factorial[-1] * i % mod) inverse.append(pow(factorial[-1], mod - 2, mod)) def comb(n, r, mod): if n < r or r < 0: return 0 elif r == 0: return 1 return factorial[n] * inverse[r] * inverse[n - r] % mod a=a[::-1] for i in range(n-k+1): ans += (a[i] * comb(n-i-1, k-1, mod))%mod a=a[::-1] for i in range(n-k+1): ans -= (a[i] * comb(n-i-1, k-1, mod))%mod print((ans%mod))
p02804
from collections import deque N, K = list(map(int, input().split())) A = [int(x) for x in input().split()] A = sorted(A) B = deque() C = deque() mod = (10**9)+7 for h in range(N): B.append(A[h]) C.append(A[h]) def cmb(n, r): # 【Python】組み合わせ(nCr) 計算の高速化より引用 if (r < 0 or r > n): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod N_cmb = 10**5 g1 = [1, 1] # 元テーブル g2 = [1, 1] # 逆元テーブル inverse = [0, 1] # 逆元テーブル計算用テーブル for ZZZ in range(2, N_cmb + 1): g1.append((g1[-1] * ZZZ) % mod) inverse.append((-inverse[mod % ZZZ] * (mod//ZZZ)) % mod) g2.append((g2[-1] * inverse[-1]) % mod) ans = 0 for i in range(N): if N - i >= K: kari = cmb(N - i - 1, K-1) % mod # print(kari) ans += (kari * B.pop()) % mod ans -= (kari * C.popleft()) % mod ans = ans % mod print(ans)
from collections import deque N, K = list(map(int, input().split())) A = [int(x) for x in input().split()] A = sorted(A) B = deque() C = deque() mod = (10**9)+7 for h in range(N): B.append(A[h]) C.append(A[h]) def cmb(n, r): # 【Python】組み合わせ(nCr) 計算の高速化より引用 if (r < 0 or r > n): return 0 r = min(r, n-r) return fac[n] * finv[r] * finv[n-r] % mod N_cmb = 10**5 # 入力の制約によって変えるところ、nCrの計算で欲しいnの最大値 fac = [1, 1] # 階乗テーブル finv = [1, 1] # 逆元テーブル inverse = [0, 1] # 逆元テーブル計算用テーブル for ZZZ in range(2, N_cmb + 1): fac.append((fac[-1] * ZZZ) % mod) inverse.append(mod-inverse[mod % ZZZ]*(mod//ZZZ) % mod) finv.append((finv[-1] * inverse[-1]) % mod) ans = 0 for i in range(N): if N - i >= K: kari = cmb(N - i - 1, K-1) % mod # print(kari) ans += (kari * B.pop()) % mod ans -= (kari * C.popleft()) % mod ans = ans % mod print(ans)
p02804
N, K=(int(i) for i in input().split()) A=[int(i) for i in input().split()] A= sorted(A) from math import factorial inf=10**9+7 ans=0 for i in range(K, N+1): #(N-1)C(K-1) ans+=(A[i-1]*factorial(i-1) // factorial(K-1) // factorial(i-1-K+1))%inf for i in range(1, N-K+2): #(N-i)C(K-1) ans-=(A[i-1]*factorial(N-i) // factorial(K-1) // factorial(N-i-K+1))%inf print((ans%inf))
N, K=(int(i) for i in input().split()) A=[int(i) for i in input().split()] A= sorted(A) from math import factorial inf=10**9+7 ans=0 def cmb(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % p p = 10 ** 9 + 7 fact = [1, 1] # fact[n] = (n! mod p) factinv = [1, 1] # factinv[n] = ((n!)^(-1) mod p) inv = [0, 1] # factinv 計算用 for i in range(2, N + 1): fact.append((fact[-1] * i) % p) inv.append((-inv[p % i] * (p // i)) % p) factinv.append((factinv[-1] * inv[-1]) % p) for i in range(K, N+1): #(N-1)C(K-1) ans+=(A[i-1]*cmb(i-1, K-1,p))%inf for i in range(1, N-K+2): #(N-i)C(K-1) ans-=(A[i-1]*cmb(N-i, K-1,p))%inf print((ans%inf))
p02804
def main(): def modinv(a, mod=10**9+7): return pow(a, mod-2, mod) def comb(n, r, mod=10**9+7): r = min(r, n-r) res = 1 for i in range(r): res = res * (n - i) * modinv(i+1, mod) % mod return res import sys input = sys.stdin.readline mod = 10**9+7 n,k = [int(i) for i in input().split()] a = [int(i) for i in input().split()] a = sorted(a) a = tuple(a) ans = 0 for i in range(0,n-k+1): p = a[i]*comb(n-1-i,k-1,mod) ans -= (p%mod) ans %= mod for i in range(k-1,n): q = a[i]*comb(i,k-1,mod) ans += (q%mod) ans %= mod print(ans) if __name__ == '__main__': main()
def make_array_for_comb(N, mod=10**9+7): fact = [1,1] fact_inv = [1,1] inv = [0,1] for i in range(2, N+1): fact.append((fact[-1]*i) % mod) # モジュラ逆数の性質 inv.append((-inv[mod%i] * (mod//i)) % mod) fact_inv.append((fact_inv[-1]*inv[i]) % mod) return fact, fact_inv def comb(n, r, mod=10**9+7): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * fact_inv[r] * fact_inv[n-r] % mod import sys input = sys.stdin.readline mod = 10**9+7 n,k = [int(i) for i in input().split()] fact, fact_inv = make_array_for_comb(n,mod) a = [int(i) for i in input().split()] a = sorted(a) a = tuple(a) ans = 0 for i in range(0,n-k+1): p = a[i]*comb(n-1-i,k-1,mod) ans -= (p%mod) ans %= mod for i in range(k-1,n): q = a[i]*comb(i,k-1,mod) ans += (q%mod) ans %= mod print(ans)
p02804
n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) MOD = 1000000007 def pow(x, y): if y == 0: return 1 ans = 1 while y > 1: if y % 2 != 0: ans *= x ans %= MOD x *= x x %= MOD y //= 2 return ans * x % MOD def mod_inv(x): return pow(x, MOD - 2) ans = 0 xCk_1 = {} for i in range(k - 1, n): if i == k - 1: xCk_1[i] = 1 else: xCk_1[i] = i * xCk_1[i - 1] * mod_inv(i - k + 1) ans += ((a[i] - a[n - i - 1]) % MOD) * xCk_1[i] ans %= MOD print(ans)
n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) MOD = 1000000007 def pow(x, y): if y == 0: return 1 ans = 1 while y > 1: if y % 2 != 0: ans *= x ans %= MOD x *= x x %= MOD y //= 2 return ans * x % MOD def mod_inv(x): return pow(x, MOD - 2) ans = 0 xCk_1 = {} for i in range(k - 1, n): if i == k - 1: xCk_1[i] = 1 else: xCk_1[i] = (((i * xCk_1[i - 1]) % MOD) * mod_inv(i - k + 1)) % MOD ans += ((a[i] - a[n - i - 1]) % MOD) * xCk_1[i] ans %= MOD print(ans)
p02804
# https://atcoder.jp/contests/abc151/tasks/abc151_e def calc(x,y): a = fac[x] b = fac[y] c = fac[x-y] ret = ( (a%p)*pow(b,p-2,p)*pow(c,p-2,p))%p return ret N,K=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() p=10**9+7 fac=[1] for i in range(1,N+1): fac.append( (fac[-1]*i)%p ) #print(fac) ans=0 for L in range(N-K+1): for R in range(L+K-1,N): if L==R: tmp=0 diff=0 #print(L,R,diff) elif L+(K-1)==R: diff= A[R]-A[L] ans += diff #print(L,R,diff) else: tmp = calc(R-L-1,K-2) diff= tmp*(A[R]-A[L]) ans += diff #print(L,R,diff) ans %=p print(ans)
# https://atcoder.jp/contests/abc151/tasks/abc151_e def calc(x,y): a = fac[x] b = fac[y] c = fac[x-y] ret = ( (a%p)*pow(b,p-2,p)*pow(c,p-2,p))%p return ret N,K=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() p=10**9+7 fac=[1] for i in range(1,N+1): fac.append( (fac[-1]*i)%p ) #print(fac) ans=0 for i in range(N): if i<=N-K: nokori = N-1-i kumi = calc(nokori,K-1) ans -= (A[i]*kumi)%p if i>=K-1: nokori = i kumi = calc(nokori,K-1) ans += (A[i]*kumi)%p print((ans%p)) #for L in range(N-K+1): # for R in range(L+K-1,N): # if L==R: # tmp=0 # diff=0 # #print(L,R,diff) # elif L+(K-1)==R: # diff= A[R]-A[L] # ans += diff # #print(L,R,diff) # else: # tmp = calc(R-L-1,K-2) # diff= tmp*(A[R]-A[L]) # ans += diff # #print(L,R,diff) # ans %=p
p02804
import math def combinations_count(n, r): a = 1 b = 1 if (n != 0) & (n >= r): for i in range(n, n - r, -1): a *= i b *= i - n + r return a // b else: return 0 n, k = list(map(int, input().split())) a = [int(i) for i in input().split()] a.sort() mod = 10 ** 9 + 7 ans = 0 for index, value in enumerate(a): ans += (combinations_count(index, k - 1) - combinations_count(n - index - 1, k - 1)) * value % mod print((ans % mod))
n, k = list(map(int, input().split())) a = [int(i) for i in input().split()] a.sort() mod = 10 ** 9 + 7 ans = 0 f = [1] * (n + 1) inv = [1] * (n + 1) for i in range(1, n + 1): f[i] = (f[i - 1] * i) % (mod) inv[n] = pow(f[n], mod - 2, mod) for i in range(n - 1, 0, -1): inv[i] = inv[i + 1] * (i + 1) % mod def combination(n, r): if (n != 0) & (n >= r): return f[n] * inv[r] * inv[n - r] % mod return 0 ans = 0 for index, value in enumerate(a): ans += (combination(index, k - 1) - combination(n - index - 1, k - 1)) * value print((ans % mod))
p02804
import math def comb(n,r,m): if r == 0: return 1 return math.factorial(n)*pow(f,m-2,m)*pow(math.factorial(n-r),m-2,m) N,K,*a = list(map(int, open(0).read().split())) m = 1000000007 f = math.factorial(K-1) a.sort() ans = 0 if K == 1: print((0)) else: for i in range(1,N-K+2): ans = (ans + a[-i] * comb(N-i,K-1,m)) % m for i in range(1,N-K+2): ans = (ans - a[i-1] * comb(N-i,K-1,m)) % m print(ans)
def memfact(a,m): temp = 1 yield temp for i in range(1,a+1): temp = temp * i % m yield temp def comb(n,r,m): if r == 0: return 1 return memf[n]*pow(memf[r],m-2,m)*pow(memf[n-r],m-2,m) N,K,*a = list(map(int, open(0).read().split())) m = 1000000007 memf = [] mfappend = memf.append for x in memfact(N-1,m): mfappend(x) a.sort() ans = 0 if K == 1: print((0)) else: for i in range(1,N-K+2): ans = (ans + a[-i] * comb(N-i,K-1,m)) % m for i in range(1,N-K+2): ans = (ans - a[i-1] * comb(N-i,K-1,m)) % m print(ans)
p02804
SIZE=10**5+1; MOD=10**9+7 #998244353 #ここを変更する SIZE += 1 inv = [0]*SIZE # inv[j] = j^{-1} mod MOD fac = [0]*SIZE # fac[j] = j! mod MOD finv = [0]*SIZE # finv[j] = (j!)^{-1} mod MOD inv[1] = 1 fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 for i in range(2,SIZE): inv[i] = MOD - (MOD//i)*inv[MOD%i]%MOD fac[i] = fac[i-1]*i%MOD finv[i]= finv[i-1]*inv[i]%MOD def choose(n,r): # nCk mod MOD の計算 if 0 <= r <= n: return (fac[n]*finv[r]%MOD)*finv[n-r]%MOD else: return 0 def chofuku(ball,box): # nHk mod MOD の計算 return choose(box+ball-1,box) N,K=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() ans=0 for i in range(N): for j in range(i+K-1,N): ans+=(A[j]-A[i])*choose(j-i-1,K-2) ans%=MOD print(ans)
SIZE=10**5+1; MOD=10**9+7 #998244353 #ここを変更する SIZE += 1 inv = [0]*SIZE # inv[j] = j^{-1} mod MOD fac = [0]*SIZE # fac[j] = j! mod MOD finv = [0]*SIZE # finv[j] = (j!)^{-1} mod MOD inv[1] = 1 fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 for i in range(2,SIZE): inv[i] = MOD - (MOD//i)*inv[MOD%i]%MOD fac[i] = fac[i-1]*i%MOD finv[i]= finv[i-1]*inv[i]%MOD def choose(n,r): # nCk mod MOD の計算 if 0 <= r <= n: return (fac[n]*finv[r]%MOD)*finv[n-r]%MOD else: return 0 def chofuku(ball,box): # nHk mod MOD の計算 return choose(box+ball-1,box) N,K=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() smax=0 smin=0 for i in range(N): smax+=A[i]*choose(i,K-1) smax%=MOD smin+=A[i]*choose(N-i-1,K-1) smin%=MOD print(((smax-smin)%MOD))
p02804
n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort() mod=10**9+7 MAX_N=n+5 fac = [1,1] + [0]*MAX_N finv = [1,1] + [0]*MAX_N inv = [0,1] + [0]*MAX_N for i in range(2,MAX_N): fac[i] = fac[i-1] * i % mod inv[i] = mod - inv[mod % i] * (mod // i) % mod finv[i] = finv[i-1] * inv[i] % mod def nCk(n,k): if n<k: return 0 if n<0 or k<0: return 0 return fac[n] * (finv[k] * finv[n-k] % mod) % mod max_x=0 for i in range(k-1,n): max_x+=a[i]*nCk(i,k-1) max_x%=mod min_x=0 for i in range(n-k+1): min_x+=a[i]*nCk(n-i-1,k-1) min_x%=mod print(((max_x-min_x)%mod))
from sys import stdin nii=lambda:list(map(int,stdin.readline().split())) lnii=lambda:list(map(int,stdin.readline().split())) n,k=nii() a=lnii() a.sort() mod=10**9+7 MAX_N = n+5 fac = [1,1] + [0]*MAX_N finv = [1,1] + [0]*MAX_N inv = [0,1] + [0]*MAX_N for i in range(2,MAX_N): fac[i] = fac[i-1] * i % mod inv[i] = mod - inv[mod % i] * (mod // i) % mod finv[i] = finv[i-1] * inv[i] % mod def nCk(n,k): if n<k: return 0 if n<0 or k<0: return 0 return fac[n] * (finv[k] * finv[n-k] % mod) % mod min_X=0 for i in range(n-k+1): min_X+=a[i]*nCk(n-i-1,k-1) min_X%=mod max_X=0 for i in range(k-1,n): max_X+=a[i]*nCk(i,k-1) max_X%=mod ans=max_X-min_X ans%=mod print(ans)
p02804
from operator import mul from functools import reduce def cmb(n,r): r = min(n-r,r) if r == 0: return 1 over = reduce(mul, list(range(n, n - r, -1))) under = reduce(mul, list(range(1,r + 1))) return over // under N,K=list(map(int,input().split())) A=list(map(int,input().split())) MOD=10**9+7 A.sort() ans=0 for i in range(N-K+1): ans+=A[-(i+1)]*cmb(N-(1+i),K-1) ans=ans%MOD ans-=A[i]*cmb(N-(1+i),K-1) ans=ans%MOD print(ans)
N,K=list(map(int,input().split())) A=list(map(int,input().split())) MOD=10**9+7 A.sort() fac=[None for i in range(N)] finv=[None for i in range(N)] inv=[None for i in range(N)] def COMinit(num): global fac global finv global inv fac[0]=1 fac[1]=1 finv[0]=1 finv[1]=1 inv[1]=1 for i in range(2,num): fac[i] = fac[i-1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i-1] * inv[i] % MOD def COM(n,k): if n<k: return 0 elif n<0 or k<0: return 0 else: return int(fac[n] * (finv[k] * finv[n - k] % MOD) % MOD) ans=0 COMinit(N) for i in range(N-K+1): ans+=A[-(i+1)]*COM(N-(1+i),K-1) ans=ans%MOD ans-=A[i]*COM(N-(1+i),K-1) ans=ans%MOD print(ans)
p02804
def main(): n,k = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() mod=10**9+7 sum=0 def we_want(x): ans=1 for i in range(k-1): ans=ans*(x-i)*pow(i+1,mod-2,mod)%mod return ans def check_min(i): if n-i>=k: minf=-we_want(n-1-i)*A[i] return minf else:return 0 def check_max(i): if i>=k-1: maxf=we_want(i)*A[i] return maxf else:return 0 for i in range(len(A)): sum+=check_min(i)+check_max(i) sum%=mod print((sum%mod)) if __name__=='__main__': main()
n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) mod = 10 ** 9 + 7 b = 1 ans = 0 for i in range(k - 1, n): ans += b * (a[i] - a[n - i - 1]) ans %= mod b = (i+1)*pow(i-k+2, mod - 2, mod) * b % mod print(ans)
p02804
import math MOD = 10 ** 9 + 7 def comb(n, r): if (r < 0) or n < r: return 0 return math.factorial(n) // (math.factorial(n - r) * math.factorial(r)) def solve(N, K, A): A.sort() ans = 0 for i in range(1, N): now = comb(i, K - 1) ans += A[i] * now A.sort(reverse=True) for i in range(1, N): now = comb(i, K - 1) ans += A[i] * (-now) return ans % MOD # N = int(input()) # S = input() N, K = list(map(int, input().split())) A = list(map(int, input().split())) print((solve(N, K, A)))
MOD = 10 ** 9 + 7 def solve(N, K, A): A.sort() ans = 0 for i in range(1, N): now = cmb(i, K - 1, MOD) ans += A[i] * now A.sort(reverse=True) for i in range(1, N): now = cmb(i, K - 1, MOD) ans += A[i] * (-now) return ans % MOD # N = int(input()) # S = input() N, K = list(map(int, input().split())) A = list(map(int, input().split())) def cmb(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % p p = 10 ** 9 + 7 fact = [1, 1] factinv = [1, 1] inv = [0, 1] for i in range(2, N + 1): fact.append((fact[-1] * i) % p) inv.append((-inv[p % i] * (p // i)) % p) factinv.append((factinv[-1] * inv[-1]) % p) print((solve(N, K, A)))
p02804
def combination(n, k, MOD): if(k > n or k < 0): return 0 frac = [1]*(n+1) for i in range(1, n+1): frac[i] = (frac[i-1]*i)%MOD return (frac[n]*pow(frac[k], MOD-2, MOD)*pow(frac[n-k], MOD-2, MOD))%MOD N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() MOD = 10**9+7 ans = 0 for i in range(N): ans = (ans + A[i]*combination(i, K-1, MOD))%MOD for i in range(N): ans = (ans - A[i]*combination(N-i-1, K-1, MOD))%MOD print(ans)
N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() MOD = 10**9+7 #c[i] := (i)C(K-1) c = [0] * (N+1) #frac[i] = i!%MOD frac = [1] * (N+1) for i in range(1, N+1): frac[i] = (frac[i-1]*i)%MOD for i in range(1, N+1): if(i >= K-1): c[i] = frac[i]*pow(frac[K-1], MOD-2, MOD)*pow(frac[i-K+1], MOD-2, MOD)%MOD ans = 0 for i in range(N): ans = (ans + A[i]*c[i])%MOD for i in range(N): ans = (ans - A[i]*c[N-i-1])%MOD print(ans)
p02804
n,k=list(map(int,input().split())) a=list(map(int,input().split())) a=sorted(a) mod=10**9+7 from operator import mul from functools import reduce def cmb(n,r): r=min(n-r,r) if r==0: return 1 else: over=reduce(mul,list(range(n,n-r,-1))) under=reduce(mul,list(range(1,r+1))) return over//under ans=0 for i in range(n-k+1): ans+=cmb(k+i-1,k-1)*(a[k-1+i]-a[n-k-i]) print((ans%mod))
n,k=list(map(int,input().split())) a=list(map(int,input().split())) a=sorted(a) mod=10**9+7 ans=0 f=[1] for i in range(1,n+1): f.append((f[-1]*i)%mod) for i in range(n-k+1): ans+=(f[k+i-1]*pow(f[i],mod-2,mod)*pow(f[k-1],mod-2,mod))*(a[k-1+i]-a[n-k-i]) print((ans%mod))
p02804
N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() mod = 10 ** 9 + 7 f = [1, 1] for i in range(2, N+1): f.append(f[i-1] * i) fk = pow(f[K-1], mod - 2, mod) total = 0 for i in range(N - K + 1): p = N - i - 1 q = K - 1 c = (f[p] * fk * pow(f[p-q], mod-2, mod)) % mod total += c * (A[-1 - i] - A[i]) total %= mod print(total)
N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() mod = 10 ** 9 + 7 f = [i for i in range(N+1)] for i in range(2, N+1): f[i] *= f[i-1] f[i] %= mod f[0] = 1 q = K - 1 fk = pow(f[q], mod - 2, mod) total = 0 for i in range(N - K + 1): p = N - i - 1 c = (f[p] * fk * pow(f[p-q], mod-2, mod)) % mod total += c * (A[-1 - i] - A[i]) total %= mod print(total)
p02804
MOD=10**9+7 n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort(reverse=True) fact = [1] fact_inv = [1] mod=10**9+7 for i in range(10**5+1): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod c=[] for i in range(1,n-k+1+1): c.append(mod_comb_k(n-i,k-1,MOD)) lc=len(c) #print(c,a) sum=0 for i in range(lc): sum+=c[i]*(a[i]-a[-i-1])%MOD print((sum%MOD))
MOD=10**9+7 n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort(reverse=True) #前計算 fact = [1] fact_inv = [1] mod=10**9+7 for i in range(n+1): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod #前計算終わり c=[] for i in range(1,n-k+1+1): c.append(mod_comb_k(n-i,k-1,MOD)) lc=len(c) sum=0 for i in range(lc): sum+=c[i]*(a[i]-a[-i-1])%MOD print((sum%MOD))
p02804
MOD=10**9+7 n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort(reverse=True) #前計算 fact = [1] fact_inv = [1] mod=10**9+7 for i in range(n+1): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod #前計算終わり c=[] for i in range(1,n-k+1+1): c.append(mod_comb_k(n-i,k-1,MOD)) lc=len(c) sum=0 for i in range(lc): sum+=c[i]*(a[i]-a[-i-1])%MOD print((sum%MOD))
MOD=10**9+7 n,k=list(map(int,input().split())) a=sorted(list(map(int,input().split())),reverse=True) #---------------------------------------------------------- # nCk mod 10**9+7 # 前計算 fact=[1] fact_inv=[1] mod=10**9+7 for i in range(n+1): new_fact=fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n]*fact_inv[k]%mod*fact_inv[n-k]%mod #---------------------------------------------------------- c=[] for i in range(1,n-k+1+1): c.append(mod_comb_k(n-i,k-1,MOD)) lc=len(c) sum=0 for i in range(lc): sum+=c[i]*(a[i]-a[-i-1])%MOD print((sum%MOD))
p02804
P = 10**9+7 N, K = list(map(int, input().split())) S = list(map(int, input().split())) S.sort() ans = 0 c = 1 for i in range(N-K+1): ans += (S[K-1+i]*c)%P ans -= (S[N-K-i]*c)%P ans %= P c = c*(K+i)//(i+1) print(ans)
P = 10**9+7 N, K = list(map(int, input().split())) S = list(map(int, input().split())) S.sort() ans = 0 c = 1 for i in range(N-K+1): ans += (S[K-1+i]*c)%P ans -= (S[N-K-i]*c)%P ans %= P c = c*(K+i)*pow(i+1, P-2, P)%P print(ans)
p02804
N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 1000000007 def combinations(n, r): r = min(r, n - r) num = 1 den = 1 for i in range(1, r + 1): num = num * (n + 1 - i) % MOD den = den * i % MOD return num * pow(den, MOD - 2, MOD) % MOD A.sort() max_sum = 0 min_sum = 0 for i, a in enumerate(A): # max if i >= K - 1: max_sum += a * combinations(i, K - 1) # min if i <= N - K: min_sum += a * combinations(N - i - 1, K - 1) print((int((max_sum - min_sum) % MOD)))
N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 1000000007 def combinations(n, r, MOD): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * fact_inv[r] * fact_inv[n - r] % MOD A.sort() fact = [1, 1] fact_inv = [1, 1] inv = [0, 1] for i in range(2, N + 1): fact.append((fact[-1] * i) % MOD) inv.append((-inv[MOD % i] * (MOD // i)) % MOD) fact_inv.append((fact_inv[-1] * inv[-1]) % MOD) max_sum = 0 min_sum = 0 for i, a in enumerate(A): # max if i >= K - 1: max_sum += a * combinations(i, K - 1, MOD) # min if i <= N - K: min_sum += a * combinations(N - i - 1, K - 1, MOD) print((int((max_sum - min_sum) % MOD)))
p02804
import sys input = sys.stdin.readline N, K = list(map(int, input().split())) a = list(map(int, input().split())) mod = 10 ** 9 + 7 res = 0 a.sort() cs = [0] * (N + 1) for i in range(N): cs[i + 1] = cs[i] + a[i] #print(cs) class Factorial: def __init__(self, n, mod): self.f = [1] for i in range(1, n + 1): self.f.append(self.f[-1] * i % mod) self.i = [pow(self.f[-1], mod - 2, mod)] for i in range(1, n + 1)[: : -1]: self.i.append(self.i[-1] * i % mod) self.i.reverse() def factorial(self, i): return self.f[i] def ifactorial(self, i): return self.i[i] def combi(self, n, k): return self.f[n] * self.i[n - k] % mod * self.i[k] % mod f = Factorial(N, mod) t = [0] * (N + 1) for i in range(1, N + 1): if i - 1 < K - 2: continue x = f.combi(i - 1, max(K - 2, 0)) y = -cs[i] + cs[-1] - cs[-1 - i] t[i] = x * y % mod res += t[i] res %= mod #print(t) print(res)
import sys input = sys.stdin.readline N, K = list(map(int, input().split())) a = list(map(int, input().split())) mod = 10 ** 9 + 7 a.sort() class Factorial: def __init__(self, n, mod): self.mod = mod self.f = [1] for i in range(1, n + 1): self.f.append(self.f[-1] * i % mod) self.i = [pow(self.f[-1], mod - 2, mod)] for i in range(1, n + 1)[: : -1]: self.i.append(self.i[-1] * i % mod) self.i.reverse() def factorial(self, i): return self.f[i] def ifactorial(self, i): return self.i[i] def combi(self, n, k): return self.f[n] * self.i[n - k] % self.mod * self.i[k] % self.mod def permi(self, n, k): return self.f[n] * self.i[n - k] % self.mod f = Factorial(N, mod) res = 0 for l in range(N - K + 1): res -= f.combi(N - l - 1, K - 1) * a[l] res %= mod for r in range(K - 1, N): res += f.combi(r, K - 1) * a[r] res %= mod print(res)
p02804
from heapq import heappush, heappop from collections import deque import re import math import functools import itertools import fractions def sRaw(): return input().rstrip("\r") def iRaw(): return int(eval(input())) def ssRaw(): return input().split() def isRaw(): return list(map(int, ssRaw())) INF = 1 << 29 def mk1d(n, val=INF): return [val for i in range(n)] def mk2d(h, w, val=INF): return [[val for i in range(w)]for i in range(h)] DIV = 998244353 def gcd(a, b): if(b == 0): return a return gcd(b, a % b) def lcm_base(x, y): return (x * y) // fractions.gcd(x, y) def lcm(*numbers): return functools.reduce(lcm_base, numbers, 1) def floyd_warshall(costs): N = len(costs) for k in range(N): for i in range(N): for j in range(N): costs[i][j] = min(costs[i][j], costs[i][k]+costs[k][j]) return costs def lcm_list(numbers): return functools.reduce(lcm_base, numbers, 1) DIV = (10**9) + 7 def mod_inv_prime(a, mod=DIV): return pow(a, mod-2, mod) def mod_inv(a, b): r = a w = b u = 1 v = 0 while w != 0: t = r//w r -= t*w r, w = w, r u -= t*v u, v = v, u return (u % b+b) % b def ncr(n, r, mod=DIV): r = min(r, n-r) ret = 1 for i in range(1, r+1): ret = ret * (n-i+1) % mod ret = ret * mod_inv(i, mod) % mod return ret def main(): N,K = isRaw() As = isRaw() As.sort() dp = [0]*N dp[K-1] = As[K-1]-As[0] for n in range(K,N): dp[n] = dp[n-1] for idx in range(n-K+2): nCk = ncr(n-idx-1,K-2) dp[n] = (dp[n]+nCk*(As[n]-As[idx])+DIV)%DIV return dp[N-1] if __name__ == "__main__": print((main()))
def sRaw(): return input().rstrip("\r") def iRaw(): return int(eval(input())) def ssRaw(): return input().split() def isRaw(): return list(map(int, ssRaw())) INF = 1 << 29 DIV = (10**9) + 7 def mod_inv_prime(a, mod=DIV): return pow(a, mod-2, mod) def mod_inv(a, b): r = a w = b u = 1 v = 0 while w != 0: t = r//w r -= t*w r, w = w, r u -= t*v u, v = v, u return (u % b+b) % b def CONV_TBL(max,mod=DIV): fac,finv,inv = [0]*max, [0]*max, [0]*max fac[0]=fac[1]=1 finv[0]=finv[1]=1 inv[1]=1 for i in range(2,max): fac[i] = fac[i-1]*i % mod inv[i] = mod -inv[mod%i] * (mod//i)%mod finv[i] = finv[i-1]*inv[i]%mod class CONV: def __init__(self): pass def ncr(self,n,k): if(n<k): return 0 if(n<0 or k<0 ): return 0 return fac[n]*(finv[k]*finv[n-k]%mod)%mod return CONV() def main(): n,k = isRaw() As = list(isRaw()) As.sort() ct = CONV_TBL(n) ans = 0 for i in range(n): ans += As[i]*ct.ncr(i, k-1) - As[i]*ct.ncr(n-(i+1), k-1) ans = ans%DIV return ans if __name__ == "__main__": print((main()))
p02804
import itertools N, K = (int(x) for x in input().split()) As = (int(x) for x in input().split()) def f(S): m = 1000000001 M = -1000000001 for a in S: m = min(m, a) M = max(M, a) return M - m Ss = list(itertools.combinations(As, K)) answer = 0 for S in Ss: answer = answer + f(S) print((answer % 1000000007))
import itertools N, K = (int(x) for x in input().split()) As = (int(x) for x in input().split()) def f(S): m = 1000000001 M = -1000000001 for a in S: m = min(m, a) M = max(M, a) return M - m answer = 0 for S in itertools.combinations(As, K): answer = answer + f(S) print((answer % 1000000007))
p02804
import itertools mod = 10**9 +7 n,k = [int(i) for i in input().split()] l = [int(i) for i in input().split()] f = list(itertools.combinations(l, k)) ans = 0 for i in f: ans += (max(i) - min(i)) print((ans%mod))
import itertools mod = 10**9 +7 n,k = [int(i) for i in input().split()] l = [int(i) for i in input().split()] f = itertools.combinations(l, k) ans = 0 for i in f: ans += abs(i[0] - i[k-1]) print((ans%mod))
p02804
N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() p = 10 ** 9 + 7 #二項定理(nCr)を高速に計算する def cmb(n,r,p): N = 10 ** 5 + 5 #必要なサイズを指定 fact = [1,1] factinv = [1,1] inv = [0,1] for i in range(2,N+1): fact.append((fact[-1] * i) % p) inv.append((-inv[p % i] * (p // i)) % p) factinv.append((factinv[-1] * inv[-1] % p)) if (r < 0) or (n < r): return 0 r = min(r,n-r) return fact[n] * factinv[r] * factinv[n-r] % p A_max = 0 A_min = 0 for i in range(N-K+1): A_max = (A_max + (A[(K-1)+i] * cmb((K+i-1),i,p))) % p A_min = (A_min + (A[-1*(K+i)] * cmb((K+i-1),i,p))) % p #print(A_max,A_min,cmb((K+i),i,p)) ans = (A_max - A_min) if ans < 0: ans = p + ans ans %= p print(ans)
N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() mod = p = 10 ** 9 + 7 fact = [1] fact_inv = [1] for i in range(10**5+5): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod A_max = 0 A_min = 0 for i in range(N-K+1): A_max = (A_max + (A[(K-1)+i] * mod_comb_k((K+i-1),i,p))) % p A_min = (A_min + (A[-1*(K+i)] * mod_comb_k((K+i-1),i,p))) % p #print(A_max,A_min,cmb((K+i),i,p)) ans = (A_max - A_min) if ans < 0: ans = p + ans ans %= p print(ans)
p02804
def cmb1(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 #出力の制限 N = 10**6 g1 = [1, 1] # 元テーブル g2 = [1, 1] #逆元テーブル inverse = [0, 1] #逆元テーブル計算用テーブル for i in range( 2, N + 1 ): g1.append( ( g1[-1] * i ) % mod ) inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod ) g2.append( (g2[-1] * inverse[-1]) % mod ) n, k = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10**9+7 A.sort(reverse=True) max_ = 0 for i in range(n): max_ += cmb1(n-1-i, k-1, mod)*A[i] max_ %= mod min_ = 0 for i in range(n): min_ += cmb1(n-1-i, k-1, mod)*A[n-1-i] min_ %= mod ans = max_-min_ ans %= mod print(ans)
n, k =list(map(int, input().split())) A = list(map(int, input().split())) mod = 10**9+7 N = 10**5+50 fac = [1]*(N+1) finv = [1]*(N+1) for i in range(N): fac[i+1] = fac[i] * (i+1) % mod finv[-1] = pow(fac[-1], mod-2, mod) for i in reversed(list(range(N))): finv[i] = finv[i+1] * (i+1) % mod def cmb1(n, r, mod): if r <0 or r > n: return 0 r = min(r, n-r) return fac[n] * finv[r] * finv[n-r] % mod A.sort() ans = 0 for i, a in enumerate(A): M = n-1-i m = i if m >= 0: ans += a*cmb1(m, k-1, mod) if M >= 0: ans -= a*cmb1(M, k-1, mod) ans %= mod print(ans)
p02804
#import sys #input = sys.stdin.readline Q = 10**9+7 def getInv(N):#Qはmod inv = [0] * (N + 1) inv[0] = 1 inv[1] = 1 for i in range(2, N + 1): inv[i] = (-(Q // i) * inv[Q%i]) % Q return inv def getFactorialInv(N): inv = [0] * (N + 1) inv[0] = 1 inv[1] = 1 ret = [1]*(N+1) for i in range(2, N + 1): inv[i] = (-(Q // i) * inv[Q%i]) % Q ret[i] = ret[i-1]*inv[i] return ret def getFactorial(N): ret = [1]*(N+1) for i in range(2,N+1): ret[i] = ret[i-1]*i%Q return ret def main(): N, K = list(map( int, input().split())) if K == 1: print((0)) return A = list( map( int, input().split())) A.sort() ans = 0 # cnt = 1 fact = getFactorial(N) invfact = getFactorialInv(N) for i in range(K-1,N): # if i < N-1: # if A[i+1] == A[i]: # cnt += 1 # continue ans += fact[i]*invfact[K-1]%Q*invfact[i-(K-1)]%Q*A[i]%Q # print(A[i], fact[i]*invfact[K-1]%Q*invfact[i-(K-1)]%Q*cnt%Q) ans %= Q A = A[::-1] for i in range(K-1,N): # if i < N-1: # if A[i+1] == A[i]: # cnt += 1 # continue ans -= fact[i]*invfact[K-1]%Q*invfact[i-(K-1)]%Q*A[i]%Q # print(A[i], fact[i]*invfact[K-1]%Q*invfact[i-(K-1)]%Q*cnt%Q) ans %= Q print(ans) if __name__ == '__main__': main()
#import sys #input = sys.stdin.readline Q = 10**9+7 # def getInv(N):#Qはmod # inv = [0] * (N + 1) # inv[0] = 1 # inv[1] = 1 # for i in range(2, N + 1): # inv[i] = (-(Q // i) * inv[Q%i]) % Q # return inv def main(): N, K = list(map( int, input().split())) if K == 1: print((0)) return A = list( map( int, input().split())) A.sort() ans = 0 cnt = 1 for i in range(K-1,N): if i >= K: cnt *= i*pow(i-(K-1), Q-2, Q)%Q cnt %= Q ans += cnt*A[i] ans -= cnt*A[N-1-i] ans %= Q print(ans) if __name__ == '__main__': main()
p02804
def cmb(a,b,c): b = min(b,a-b) num = 1 for i in range(b): num = num*(a-i) % c den = 1 for i in range(b): den = den*(i+1) % c return num * pow(den,c-2,c) % c mod = 10**9 + 7 n,k = list(map(int,input().split())) inv = [0,1] for i in range(2,n): inv += [inv[mod % i]*(mod - mod//i) % mod] a = list(map(int,input().split())) a.sort() ans = 0 c = cmb(n-1,k-1,mod) if k == 1: print((0)) exit() for i in range(n-k+1): ans -= a[i] * c ans += a[-i-1] * c ans %= mod c = c*(n-k-i)*inv[n-i-1] if ans < 0: ans += mod print(ans)
def cmb(a,b,c): b = min(b,a-b) num = 1 for i in range(b): num = num*(a-i) % c den = 1 for i in range(b): den = den*(i+1) % c return num * pow(den,c-2,c) % c mod = 10**9 + 7 n,k = list(map(int,input().split())) inv = [0,1] for i in range(2,n): inv += [inv[mod % i]*(mod - mod//i) % mod] a = list(map(int,input().split())) a.sort() ans = 0 c = 1 x = 1 if k == 1: print((0)) exit() for i in range(n-k+1): ans -= a[n-k-i] * c ans += a[k+i-n-1] * c ans %= mod c = c*(i+k)*inv[i+1] % mod if ans < 0: ans += mod print(ans)
p02804
n, k = list(map(int, input().split())) a = list(map(int, input().split())) mod = int(1e+9 + 7) a = sorted(a) kai = [1, 1] gyaku = [1, 1] for i in range(2, n+1): kai.append(kai[-1]*i % mod) gyaku.append(gyaku[-1]*pow(i, mod-2, mod)) answer = 0 for i in range(n-k+1): for j in range(i+k-1,n): answer = (answer + (a[j] - a[i]) * kai[j-i-1] *gyaku[j-i-1-(k-2)] * gyaku[k-2])%mod if k == 1: print((0)) else: print(answer)
n, k = list(map(int, input().split())) a = list(map(int, input().split())) mod = int(1e+9 + 7) a = sorted(a) kai = [1]*(n+1) gyaku = [1]*(n+1) for i in range(2, n+1): kai[i] = kai[i-1]*i % mod gyaku[i] = gyaku[i-1]*pow(i, mod-2, mod) %mod answer = 0 for i in range(n-k+1): for j in range(i+k-1,n): answer = (answer + (a[j] - a[i]) * kai[j-i-1] *gyaku[j-i-1-(k-2)] * gyaku[k-2])%mod if k == 1: print((0)) else: print(answer)
p02804
from functools import lru_cache @lru_cache(maxsize=2**17, typed=int) def comb(n, r, p): r = min(n - r, r) if r == 0: return 1 over = 1 for i in range(n, n - r, -1): over = over * i % p under = 1 for i in range(1, r + 1): under = under * i % p inv = pow(under, p - 2, p) return over * inv % p def main(): n, k = list(map(int, input().split())) a = sorted(int(i) for i in input().split()) mod = 10**9 + 7 f = 0 for i in range(n - k + 1): f = (f + a[k + i - 1] * comb(k - 1 + i, k - 1, mod) % mod) % mod f = (f - a[i] * comb(n - 1 - i, k - 1, mod) % mod) % mod print(f) if __name__ == '__main__': main()
def main(): n, k = list(map(int, input().split())) a = sorted(int(i) for i in input().split()) mod = 10**9 + 7 comb = [1] * (n - k + 1) for i in range(n - k): comb[i + 1] = (comb[i] * (k + i) * pow(i + 1, mod - 2, mod)) % mod f = 0 for i in range(n - k + 1): f = (f + a[k + i - 1] * comb[i] % mod) % mod f = (f - a[i] * comb[-1 - i] % mod) % mod print(f) if __name__ == '__main__': main()
p02804
import sys input = sys.stdin.readline mod = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = sorted(list(map(int, input().split()))) minus = 0 plus = 0 fact = [0] * (N+1) fact[0] = 1 pow_fact = [0] * (N+1) pow_fact[0] = 1 fa = 1 for i in range(1, N+1): fa *= i fact[i] = fa pow_fact[i] = pow(fa, mod-2, mod) b = pow_fact[K-1] for i in range(N-K+1): a = fact[N-i-1] c = pow_fact[N-i-K] comb = (a*b*c) % mod minus += (A[i] * comb) plus += (A[-i-1] * comb) print(((plus - minus) % mod))
import sys input = sys.stdin.readline mod = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = sorted(list(map(int, input().split()))) minus = 0 plus = 0 fact = [0] * (N+1) fact[0] = 1 pow_fact = [0] * (N+1) pow_fact[0] = 1 fa = 1 for i in range(1, N+1): fa *= i fa %= mod fact[i] = fa pow_fact[i] = pow(fa, mod-2, mod) b = pow_fact[K-1] for i in range(N-K+1): a = fact[N-i-1] c = pow_fact[N-i-K] comb = (a*b*c) % mod minus += (A[i] * comb) % mod plus += (A[-i-1] * comb) % mod print(((plus - minus) % mod))
p02804
import itertools as it n, k = list(map(int, input().split())) a = list(map(int, input().split())) a.sort() ans=0 for i in it.combinations([i for i in range(n)], k): max_x = a[max(i)] min_x = a[min(i)] ans += (max_x - min_x) print((ans%(10**9 +7)))
class Combination(): # nCr(mod p) #n<=10**6 def __init__(self, N, MOD): # cmbの前処理 self.mod = MOD self.FACT = [1, 1] # 階乗 self.INV = [0, 1] # 各iの逆元 self.FACTINV = [1, 1] # 階乗の逆元 for i in range(2, N + 1): self.FACT.append((self.FACT[-1] * i) % self.mod) self.INV.append(pow(i, self.mod - 2, self.mod)) self.FACTINV.append((self.FACTINV[-1] * self.INV[-1]) % self.mod) def count(self, N, R): # nCr(mod p) #前処理必要 if (R < 0) or (N < R): return 0 R = min(R, N - R) return self.FACT[N] * self.FACTINV[R] * self.FACTINV[N-R] % self.mod n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) mod = 10 ** 9 + 7 ans = 0 cmb = Combination(n, mod) for i in range(n): cnt = cmb.count(i, k - 1) - cmb.count(n - i - 1, k - 1) ans += a[i] * cnt % mod print((ans % mod))
p02804
n,k=list(map(int,input().split())) a=sorted(list(map(int,input().split()))) mod = 10**9+7 # 変える fac = [1]*n finv = [1]*n inv = [0]*n inv[1] = 1 for i in range(2,n): fac[i] = fac[i-1]*i % mod inv[i] = mod - inv[mod%i] *(mod//i) %mod finv[i] = finv[i-1] * inv[i] % mod def comb(n,k): if n<k: return 0 if n<0 or k<0: return 0 return fac[n]*(finv[k] * finv[n-k] % mod)%mod ans=0 for i in range(n-k+1): ans+=comb(n-i-1,k-1)*(a[n-i-1]-a[i]) print((ans%mod))
n,k=list(map(int,input().split())) a=sorted(list(map(int,input().split()))) mod = 10**9+7 # 変える fac = [1]*n finv = [1]*n inv = [0]*n inv[1] = 1 for i in range(2,n): fac[i] = fac[i-1]*i % mod inv[i] = mod - inv[mod%i] *(mod//i) %mod finv[i] = finv[i-1] * inv[i] % mod def comb(n,k): if n<k: return 0 if n<0 or k<0: return 0 return fac[n]*(finv[k] * finv[n-k] % mod)%mod ans=0 for i in range(n-k+1): ans=(ans+comb(n-i-1,k-1)*(a[n-i-1]-a[i]))%mod print(ans)
p02804
# -*- coding: utf-8 -*- # E import sys from functools import reduce # 再起回数上限変更 # sys.setrecursionlimit(1000000) N, K = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10**9 + 7 A.sort() # print(A) def cmb(n, r): from operator import mul from functools import reduce r = min(n - r, r) if r == 0: return 1 over = reduce(mul, list(range(n, n - r, -1))) under = reduce(mul, list(range(1, r + 1))) return over // under ans = 0 num1=None num2=None for i in range(N): if N - i - 1 >= K-1: if num1 is None: num1 = cmb(N-i-1, K-1) % mod else: num1 = int(num1 * ((N-i-K+1) % mod) * pow(N-i, mod-2, mod)) # print(N-i-1, K-1, num1) if A[i] * num1 < 0: ans += (-A[i] * num1) % mod else: ans -= (A[i] * num1) % mod # print(f'-: {i}, {num}, {A[i]}') if i >= K-1: if num2 is None: num2 = cmb(i, K-1) % mod else: num2 = num2 * (i % mod) * pow(i-K+1, mod-2, mod) # print(i, K-1, num2) if A[i] * num2 < 0: ans -= (-A[i] * num2) % mod else: ans += (A[i] * num2) % mod # print(f'+: {i}, {num}, {A[i]}') print((ans % mod))
# -*- coding: utf-8 -*- # E N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() mod = 10**9 + 7 class Cmb(object): def cmb_precalc(self, n, r, mod: int = 10 ** 9 + 7): if (r < 0) or (r > n): return 0 r = min(r, n - r) return self.g1[n] * self.g2[r] * self.g2[n - r] % mod def cmb_prep(self, N: int, mod: int = 10 ** 9 + 7): self.g1 = [1, 1] # 元テーブル self.g2 = [1, 1] # 逆元テーブル inverse = [0, 1] # 逆元テーブル計算用テーブル for i in range(2, N + 1): self.g1.append((self.g1[-1] * i) % mod) inverse.append((-inverse[mod % i] * (mod // i)) % mod) self.g2.append((self.g2[-1] * inverse[-1]) % mod) ans = 0 cmb = Cmb() cmb.cmb_prep(N + 5) for i in range(N): if i >= K-1: ans += A[i] * cmb.cmb_precalc(i, i-K+1) if N - i - 1 >= K-1: ans -= A[i] * cmb.cmb_precalc(N-i-1, K-1) print((ans % mod))
p02804
N,K = list(map(int,input().split())) A = list(map(int,input().split())) mod = 10**9+7 import itertools ans = 0 for a in itertools.combinations(A,K): ans += (max(a)-min(a))%mod ans %= mod print(ans)
N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() fact_l=[1]*(N+10) mod = 10**9+7 for i in range(2,N+1): fact_l[i]=(fact_l[i-1]*i)%mod fact_inv_l = [1]*(N+10) for i in range(2,N+1): fact_inv_l[i]=pow(fact_l[i],mod-2,mod) ans = 0 for i in range(1,N-K+2): b = N-i c = K-1 ans -= A[i-1]*fact_l[b]%mod*fact_inv_l[b-c]%mod*fact_inv_l[c]%mod ans += A[-i]*fact_l[b]%mod*fact_inv_l[b-c]%mod*fact_inv_l[c]%mod print((ans%mod))
p02804
def factorial(n, p): ret = 1 for i in range(n, 0, -1): ret *= i ret %= p return ret def comb(n, r, p): r = min(r, n - r) a = factorial(r, p) b = factorial(n - r, p) ret = factorial(n, p) * pow(a, p - 2, p) * pow(b, p - 2, p) % p return ret mod = 10 ** 9 + 7 n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) ans = 0 sum_min = 0 for i in range(n - k + 1): cnt = comb(n - 1 - i, k - 1, mod) sum_min += a[i] * cnt sum_min %= mod a_rev = a[::-1] sum_max = 0 for i in range(n - k + 1): cnt = comb(n - 1 - i, k - 1, mod) sum_max += a_rev[i] * cnt sum_max %= mod ans = (sum_max - sum_min) % mod print(ans)
def cmb(n, r, p): if r < 0 or n < r: return 0 r = min(r, n - r) return fact[n] * fact_inv[r] * fact_inv[n - r] % p n, k = list(map(int, input().split())) a = sorted(list(map(int, input().split())), reverse=True) p = 10 ** 9 + 7 fact = [1, 1] # fact[n] = (n! mod p) fact_inv = [1, 1] # fact_inv[n] = ((n!)^(-1) mod p) inv = [0, 1] # fact_invの計算用 for i in range(2, n + 1): fact.append(fact[-1] * i % p) inv.append((-inv[p % i] * (p // i)) % p) fact_inv.append(fact_inv[-1] * inv[-1] % p) i = 0 sum_max = 0 sum_min = 0 while n - i - 1 >= k - 1: cnt = cmb(n - i - 1, k - 1, p) sum_max += a[i] * cnt sum_min += a[n - i - 1] * cnt # print(i, a[i] * cnt, a[n - i - 1] * cnt) i += 1 ans = (sum_max - sum_min) % p print(ans)
p02804
import sys,bisect input = sys.stdin.readline n,k = list(map(int,input().split())) a = list(map(int,input().split())) mod = 10**9+7 fact = [1] fact_inv = [1] for i in range(10**5+5): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod a.sort() mi = 0 for i in range(n-k+1): mi = (mi + a[i]*mod_comb_k(n-i-1,k-1,mod)%mod)%mod a = a[::-1] ma = 0 for i in range(n-k+1): ma = (ma + a[i]*mod_comb_k(n-i-1,k-1,mod)%mod)%mod print(((ma-mi)%mod))
def main(): import sys input = sys.stdin.readline n,k = list(map(int,input().split())) a = list(map(int,input().split())) mod = 10**9+7 fact = [1] fact_inv = [1] for i in range(10**5+5): new_fact = fact[-1]*(i+1)%mod fact.append(new_fact) fact_inv.append(pow(new_fact,mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod a.sort() res = 0 for i in range(n-k+1): res = (res + (a[n-1-i]- a[i])*mod_comb_k(n-i-1,k-1,mod)%mod)%mod print(res) if __name__ == '__main__': main()
p02804
def main(): import sys input = sys.stdin.readline n,k = list(map(int,input().split())) a = list(map(int,input().split())) mod = 10**9+7 fact = [1] fact_inv = [1] for i in range(10**5+5): fact.append(fact[-1]*(i+1)%mod) fact_inv.append(pow(fact[-1],mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod a.sort() res = 0 for i in range(n-k+1): res = (res + (a[n-1-i]- a[i])*mod_comb_k(n-i-1,k-1,mod)%mod)%mod print(res) if __name__ == '__main__': main()
def main(): import sys input = sys.stdin.readline n,k = list(map(int,input().split())) a = list(map(int,input().split())) mod = 10**9+7 fact = [1] fact_inv = [1] for i in range(10**5+5): fact.append(fact[-1]*(i+1)%mod) fact_inv.append(pow(fact[-1],mod-2,mod)) def mod_comb_k(n,k,mod): return fact[n] * fact_inv[k] % mod * fact_inv[n-k] %mod a.sort() res = 0 for i in range(n-k+1): res = (res + (a[n-1-i]- a[i])*mod_comb_k(n-i-1,k-1,mod))%mod print(res) if __name__ == '__main__': main()
p02804
import sys, re from collections import deque, defaultdict, Counter from math import ceil, sqrt, hypot, factorial, pi, sin, cos, tan, asin, acos, atan, radians, degrees, log2, gcd from itertools import accumulate, permutations, combinations, combinations_with_replacement, product, groupby from operator import itemgetter, mul from copy import deepcopy from string import ascii_lowercase, ascii_uppercase, digits from bisect import bisect, bisect_left, insort, insort_left from heapq import heappush, heappop from functools import reduce def input(): return sys.stdin.readline().strip() def INT(): return int(eval(input())) def MAP(): return list(map(int, input().split())) def LIST(): return list(map(int, input().split())) def ZIP(n): return list(zip(*(MAP() for _ in range(n)))) sys.setrecursionlimit(10 ** 9) INF = float('inf') mod = 10 ** 9 + 7 #mod = 998244353 from decimal import * #import numpy as np #decimal.getcontext().prec = 10 #階乗# lim = 10**5 #必要そうな階乗の限界を入力 fact = [1] * (lim+1) for n in range(1, lim+1): fact[n] = n * fact[n-1] % mod #階乗の逆元# fact_inv = [1]*(lim+1) fact_inv[lim] = pow(fact[lim], mod-2, mod) for n in range(lim, 0, -1): fact_inv[n-1] = n*fact_inv[n]%mod def C(n, r): if n < r: return 0 else: return (fact[n]*fact_inv[r]%mod)*fact_inv[n-r]%mod N, K = MAP() A = LIST() A.sort() A_cnt = Counter(A) P = list(A_cnt.keys()) p = list(A_cnt.values()) #print("P={}".format(P)) #print("p={}".format(p)) p_acc = list(accumulate(p)) p_acc_rev = list(accumulate(p[::-1])) #print("p_acc={}".format(p_acc)) #print("p_acc_rev={}".format(p_acc_rev)) n = len(p) T = [[0]*4 for _ in range(n)] for i in range(n): T[i][0] = p_acc[i] for i in range(1, n): T[i][1] = p_acc[i-1] for i in range(n): T[(-i-1)][3] = p_acc_rev[i] for i in range(1, n): T[(-i-1)][2] = p_acc_rev[i-1] #for i in range(n): # print(T[i]) t = [0]*n for idx, x in enumerate(T): t[idx] = (C(x[0], K) - C(x[1], K) + C(x[2], K) - C(x[3], K))%mod ans = 0 for i in range(n): ans = (ans + P[i]*t[i]%mod)%mod print(ans)
import sys, re from collections import deque, defaultdict, Counter from math import ceil, sqrt, hypot, factorial, pi, sin, cos, tan, asin, acos, atan, radians, degrees, log2, gcd from itertools import accumulate, permutations, combinations, combinations_with_replacement, product, groupby from operator import itemgetter, mul from copy import deepcopy from string import ascii_lowercase, ascii_uppercase, digits from bisect import bisect, bisect_left, insort, insort_left from heapq import heappush, heappop from functools import reduce def input(): return sys.stdin.readline().strip() def INT(): return int(eval(input())) def MAP(): return list(map(int, input().split())) def LIST(): return list(map(int, input().split())) def ZIP(n): return list(zip(*(MAP() for _ in range(n)))) sys.setrecursionlimit(10 ** 9) INF = float('inf') mod = 10 ** 9 + 7 #mod = 998244353 from decimal import * #import numpy as np #decimal.getcontext().prec = 10 #階乗# lim = 10**5 #必要そうな階乗の限界を入力 fact = [1] * (lim+1) for n in range(1, lim+1): fact[n] = n * fact[n-1] % mod #階乗の逆元# fact_inv = [1]*(lim+1) fact_inv[lim] = pow(fact[lim], mod-2, mod) for n in range(lim, 0, -1): fact_inv[n-1] = n*fact_inv[n]%mod def C(n, r): if n < r: return 0 else: return (fact[n]*fact_inv[r]%mod)*fact_inv[n-r]%mod N, K = MAP() A = LIST() A.sort() max_sum = 0 for i in range(K-1, N): max_sum = (max_sum + A[i]*C(i, K-1)%mod)%mod A = A[::-1] min_sum = 0 for i in range(K-1, N): min_sum = (min_sum + A[i]*C(i, K-1)%mod)%mod print(((max_sum - min_sum)%mod))
p02804
import math def nCr(n, r): return math.factorial(n) // (math.factorial(n - r) * math.factorial(r)) mod = 10**9 + 7 n, k = list(map(int, input().split())) a = list(map(int, input().split())) a.sort() a_reverse = a[::-1] plus = 0 minus = 0 cnt = 0 ind = 0 # ceil = nCr(n, k) kaisu = nCr(n, k-1) # while cnt < ceil: for _ in range(n-k+1): kaisu = kaisu * ((n-ind)-(k-1)) // (n-ind) cnt += kaisu plus = (plus + (kaisu * a_reverse[ind]) % mod) % mod minus = (minus + (kaisu * a[ind]) % mod) % mod ind += 1 print(((plus-minus) % mod))
n,k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) a_reverse = a[::-1] mod = 10**9+7 factorial = [1] inverse = [1] for i in range(1, n+2): factorial.append(factorial[-1] * i % mod) inverse.append(pow(factorial[-1], mod - 2, mod)) def comb(n, r, mod): if n < r or r < 0: return 0 elif r == 0: return 1 return factorial[n] * inverse[r] * inverse[n - r] % mod plus = 0 minus = 0 cnt = 0 ind = 0 for i in range(n-k+1): kaisu = comb(n-i-1, k-1, mod) plus = (plus + (kaisu * a_reverse[ind]) % mod) % mod minus = (minus + (kaisu * a[ind]) % mod) % mod ind += 1 print(((plus-minus) % mod))
p02804
n,k = list(map(int, input().split())) a = sorted(list(map(int, input().split()))) a_reverse = a[::-1] mod = 10**9+7 factorial = [1] inverse = [1] for i in range(1, n+1): factorial.append(factorial[-1] * i % mod) inverse.append(pow(factorial[-1], mod - 2, mod)) def comb(n, r, mod): if n < r or r < 0: return 0 elif r == 0: return 1 return factorial[n] * inverse[r] * inverse[n - r] % mod plus = 0 minus = 0 cnt = 0 ind = 0 for i in range(n-k+1): kaisu = comb(n-i-1, k-1, mod) plus = (plus + (kaisu * a_reverse[ind]) % mod) % mod minus = (minus + (kaisu * a[ind]) % mod) % mod ind += 1 print(((plus-minus) % mod))
n, k = list(map(int, input().split())) a = list(map(int, input().split())) mod = 10**9 + 7 factorial = [1] inverse = [1] for i in range(1, n+1): factorial.append(factorial[-1] * i % mod) inverse.append(pow(factorial[-1], mod - 2, mod)) def comb(n, r, mod): if n < r or r < 0: return 0 elif r == 0: return 1 return factorial[n] * inverse[r] * inverse[n - r] % mod a.sort() mini = 0 for i in range(n-1): mini += a[i] * comb(n-i-1, k-1, mod) mini %= mod a.sort(reverse=True) maxi = 0 for i in range(n-1): maxi += a[i] * comb(n-i-1, k-1, mod) maxi %= mod print(((maxi-mini)%mod))
p02804
def cmb(n, r): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % mod N = pow(10, 5) # N は必要分だけ用意する fact = [1, 1] # fact[n] = (n! mod p) factinv = [1, 1] # factinv[n] = ((n!)^(-1) mod p) inv = [0, 1] # factinv 計算用 mod = pow(10, 9) + 7 for i in range(2, N + 1): fact.append((fact[-1] * i) % mod) inv.append((-inv[mod % i] * (mod // i)) % mod) factinv.append((factinv[-1] * inv[-1]) % mod) n,k = list(map(int,input().split())) a = [int(i) for i in input().split()] a.sort() if k > 1: ans = 0 for i in range(k-1, n): for j in range(0, i - k + 2): ans += (a[i] - a[j]) * cmb(i - j - 1, k - 2) #print(j, i, ' ', a[j],a[i], ' ', a[i] - a[j]) ans %= pow(10, 9) + 7 print(ans) else: print((0))
def cmb(n, r): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % mod N = pow(10, 5) # N は必要分だけ用意する fact = [1, 1] # fact[n] = (n! mod p) factinv = [1, 1] # factinv[n] = ((n!)^(-1) mod p) inv = [0, 1] # factinv 計算用 mod = pow(10, 9) + 7 for i in range(2, N + 1): fact.append((fact[-1] * i) % mod) inv.append((-inv[mod % i] * (mod // i)) % mod) factinv.append((factinv[-1] * inv[-1]) % mod) n,k = list(map(int,input().split())) a = [int(i) for i in input().split()] a.sort() if k > 1: ans = 0 for i in range(k-1, n): maxs = a[i] ncr = cmb(i, k-1) #print(maxs, ncr, maxs * ncr) ans += maxs * ncr ans %= mod for i in range(n-k+1): mins = a[i] ncr = cmb(n-i-1, k-1) #print(mins, ncr, mins * ncr) ans -= mins * ncr ans %= mod print(ans) else: print((0))
p02804
def cmb(n, r, mod): if ( r < 0 or r > n ): return 0 r = min(r, n - r) return g1[n] * g2[r] * g2[n - r] % mod MOD = 10 ** 9 + 7 #出力の制限 N = 10 ** 5 * 2 + 1 g1 = [1, 1] # 元テーブル g2 = [1, 1] #逆元テーブル inverse = [0, 1] #逆元テーブル計算用テーブル for i in range(2, N + 1 ): g1.append((g1[-1] * i) % MOD) inverse.append((-inverse[MOD % i] * (MOD // i) ) % MOD) g2.append((g2[-1] * inverse[-1]) % MOD) N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() answer = 0 for i in range(N): if i > N - K: break answer = (answer + (A[N - i - 1] - A[i]) * cmb(N - 1 - i, K - 1, MOD)) % MOD print(answer)
N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10 ** 9 + 7 ### Combination Table ### g1 = [1, 1] # 元テーブル g2 = [1, 1] # 逆元テーブル inverse = [0, 1] # 逆元テーブル計算用テーブル def comb(n, r, mod): if r < 0 or r > n: return 0 r = min(r, n - r) return g1[n] * g2[r] * g2[n - r] % mod for i in range(2, N + 1): g1.append((g1[-1] * i) % MOD) inverse.append((-inverse[MOD % i] * (MOD // i) ) % MOD) g2.append((g2[-1] * inverse[-1]) % MOD) ######################### A.sort() answer = 0 for i in range(N): if i > N - K: break answer = (answer + (A[N - i - 1] - A[i]) * comb(N - 1 - i, K - 1, MOD)) % MOD print(answer)
p02804
MOD = 10**9 + 7 def getInvs(n, MOD): invs = [1] * (n+1) for x in range(2, n+1): invs[x] = (-(MOD//x) * invs[MOD%x]) % MOD return invs def getCombKs(n, k, invs, MOD): combKs = [0] * (n+1) combKs[k] = 1 for x in range(k+1, n+1): combKs[x] = (combKs[x-1] * x * invs[x-k]) % MOD return combKs N, K = list(map(int, input().split())) As = list(map(int, input().split())) As.sort() invs = getInvs(N, MOD) combKs = getCombKs(N, K-1, invs, MOD) ans = 0 for i, A in enumerate(As): numMax = combKs[i] numMin = combKs[N-1-i] ans += A * (numMax - numMin) % MOD ans %= MOD print(ans)
MOD = 10**9 + 7 N, K = list(map(int, input().split())) As = list(map(int, input().split())) def getInvs(n, MOD): invs = [1] * (n+1) for x in range(2, n+1): invs[x] = (-(MOD//x) * invs[MOD%x]) % MOD return invs invs = getInvs(N, MOD) def getCombKs(n, k, invs, MOD): combKs = [0] * (n+1) combKs[k] = 1 for x in range(k+1, n+1): combKs[x] = (combKs[x-1] * x * invs[x-k]) % MOD return combKs combKs = getCombKs(N, K-1, invs, MOD) As.sort() ans = 0 for i, A in enumerate(As): if i >= K-1: ans += combKs[i] * A if N-1-i >= K-1: ans -= combKs[N-1-i] * A ans %= MOD print(ans)
p02804
MAX_NUM = 10**6 + 1 MOD = 10**9+7 fac = [0 for _ in range(MAX_NUM)] finv = [0 for _ in range(MAX_NUM)] inv = [0 for _ in range(MAX_NUM)] fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 inv[1] = 1 for i in range(2,MAX_NUM): fac[i] = fac[i-1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i-1] * inv[i] % MOD def combinations(n,k): if n < k: return 0 if n < 0 or k < 0: return 0 return fac[n] * (finv[k] * finv[n-k] % MOD) % MOD N, K = list(map(int, input().split())) A = list(map(int, input().split())) A=sorted(A) ANSWER = 0 # Sの最大値をイテレート for i in range(K-1, N): for j in range(i-K+2): ANSWER += (A[i]-A[j])*combinations(i-j+1-2, K-2) ANSWER %= MOD print(ANSWER)
MAX_NUM = 10**6 + 1 MOD = 10**9+7 fac = [0 for _ in range(MAX_NUM)] finv = [0 for _ in range(MAX_NUM)] inv = [0 for _ in range(MAX_NUM)] fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 inv[1] = 1 for i in range(2,MAX_NUM): fac[i] = fac[i-1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i-1] * inv[i] % MOD def combinations(n,k): if n < k: return 0 if n < 0 or k < 0: return 0 return fac[n] * (finv[k] * finv[n-k] % MOD) % MOD N, K = list(map(int, input().split())) A = list(map(int, input().split())) A=sorted(A) ANSWER = 0 # Sの最大値をイテレート for i in range(K-1, N): ANSWER += A[i]*combinations(i, K-1) # print(ANSWER) for i in range(N-K+1): ANSWER -= A[i]*combinations(N-i-1, K-1) # print(ANSWER) ANSWER %= MOD print(ANSWER)
p02804
from operator import mul from functools import reduce def comb(n, r): r = min(n - r, r) if r == 0: return 1 over = reduce(mul, list(range(n, n - r, -1))) under = reduce(mul, list(range(1, r + 1))) return over // under n, k = list(map(int, input().split())) a = list(map(int, input().split())) a.sort() mi = [0] * n ma = [0] * n s_mi = 0 s_ma = 0 for i in range(n): nn = n - i - 1 if nn < k - 1: break else: mi[i] = comb(nn, k - 1) ma[-(i + 1)] = mi[i] for i, j, k in zip(a, mi, ma): s_mi += i * j s_ma += i * k print(((s_ma - s_mi) % (10 ** 9 + 7)))
n, k = list(map(int, input().split())) a = list(map(int, input().split())) mod = 10 ** 9 + 7 fac = {0: 1, 1: 1} finv = {0: 1, 1: 1} inv = {1: 1} a.sort() mi = [0] * n ma = [0] * n s_mi = 0 s_ma = 0 def comb_init(): for i in range(2, n + 1): fac[i] = fac[i - 1] * i % mod inv[i] = mod - inv[mod % i] * (mod // i) % mod finv[i] = finv[i - 1] * inv[i] % mod def comb(n, k): if n < k: return 0 if n < 0 or k < 0: return 0 return fac[n] * (finv[k] * finv[n - k] % mod) % mod comb_init() for i in range(n): nn = n - i - 1 if nn < k - 1: break else: mi[i] = comb(nn, k - 1) ma[-(i + 1)] = mi[i] s_mi = (s_mi + mi[i] * a[i]) % mod s_ma = (s_ma + ma[-(i + 1)] * a[-(i + 1)]) % mod print(((s_ma - s_mi) % mod))
p02804
def main(): N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() r = 0 if False: for i in range(K+1): r += (A[-i-1] - A[i]) * cmb(N-i-1, K-1, mod) else: for i in range(N-K+1): r += (A[-i-1] - A[i]) * cmb(N-i-1, K-1, mod) print((r % mod)) def cmb(n, r, mod): if r < 0 or r > n: return 0 r = min(r, n - r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 g1 = [1, 1] g2 = [1, 1] inverse = [0, 1] for i in range(2, 10 ** 6 + 1): g1.append((g1[-1] * i) % mod) inverse.append((-inverse[mod % i] * (mod // i)) % mod) g2.append((g2[-1] * inverse[-1]) % mod) main()
def main(): N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() r = 0 if False: for i in range(K+1): r += (A[-i-1] - A[i]) * cmb(N-i-1, K-1, mod) else: for i in range(N-K+1): r += (A[N-i-1] - A[i]) * cmb(N-i-1, K-1, mod) print((r % mod)) def cmb(n, r, mod): if r < 0 or r > n: return 0 r = min(r, n - r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 g1 = [1, 1] g2 = [1, 1] inverse = [0, 1] for i in range(2, 10 ** 6 + 1): g1.append((g1[-1] * i) % mod) inverse.append((-inverse[mod % i] * (mod // i)) % mod) g2.append((g2[-1] * inverse[-1]) % mod) main()
p02804
n, k = list(map(int, input().split())) a = [int(i) for i in input().split()] a.sort() total = 0 def _cmb(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 N = 10**5 g1 = [1, 1] g2 = [1, 1] inverse = [0, 1] for i in range(2, N + 1): g1.append(( g1[-1] * i ) % mod) inverse.append((-inverse[mod % i] * (mod//i)) % mod) g2.append((g2[-1] * inverse[-1]) % mod) mem = {} def cmb(n, r, mod): if (n,r) not in mem: mem[(n,r)] = _cmb(n, r, mod) return mem[(n,r)] for i in range(n-k+1): for j in range(i+k-1,n): total += cmb(j-i-1,k-2,mod)*(a[j]-a[i]) total %= mod print(total)
n, k = list(map(int, input().split())) a = [int(i) for i in input().split()] a.sort() total = 0 def cmb(n, r, mod): if (r<0 or r>n): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 N = 10**5 g1 = [1,1] g2 = [1,1] inverse = [0,1] for i in range(2, N + 1): g1.append((g1[-1]*i) % mod) inverse.append((-inverse[mod%i] * (mod//i)) % mod) g2.append((g2[-1]*inverse[-1]) % mod) for i in range(n-k+1): total += cmb(n-i-1,k-1,mod)*(a[n-i-1]-a[i]) total %= mod print(total)
p02804
from itertools import permutations, combinations n,k=list(map(int, input().split())) c=combinations(list(map(int, input().split())),k) t=sum( [max(v)-min(v) for v in list(c)] ) print((t%(10**9+7)))
from itertools import combinations n,k=list(map(int, input().split())) c=combinations(list(map(int, input().split())),k) print((sum( [max(v)-min(v) for v in c] )%(10**9+7)))
p02804
H, K = list(map(int,input().split())) A = list(map(int, input().split())) mod = int(10**9) + 7 A.sort() nCkminu1 = [1] * H for n in range(K, H): nCkminu1[n] = nCkminu1[n-1] * n // (n - (K-1)) ans = 0 for nCk, amin, amax in zip(nCkminu1[K-1:], A[:-(K-1)][::-1], A[K-1:]): ans += nCk % mod * (amax - amin) print((ans % mod))
H, K = list(map(int,input().split())) A = list(map(int, input().split())) mod = int(10**9) + 7 A.sort() nCkminu1 = [1] * H for n in range(K, H): nCkminu1[n] = nCkminu1[n-1] * n // (n - (K-1)) nCkminu1[n-1] %= mod ans = 0 for nCk, amin, amax in zip(nCkminu1[K-1:], A[:-(K-1)][::-1], A[K-1:]): ans += nCk * (amax - amin) print((ans % mod))
p02804
p = 1000000007 N, K = list(map(int, input().split())) A = list(map(int, input().split())) fac = [0] * (N + 1) fac[0] = 1 for i in range(N): fac[i + 1] = fac[i] * (i + 1) % p def mcomb(n, k): if n == 0 and k == 0: return 1 if n < k or k < 0: return 0 return fac[n] * pow(fac[n - k], p - 2, p) * pow(fac[k], p - 2, p) % p A.sort(reverse=True) result = 0 for i in range(N - K + 1): result += A[i] * mcomb(N - (i + 1), K - 1) result %= p A.reverse() for i in range(N - K + 1): result -= A[i] * mcomb(N - (i + 1), K - 1) result %= p # result += p # result %= p print(result)
# フェルマーの小定理 N, K = list(map(int, input().split())) A = list(map(int, input().split())) m = 1000000007 fac = [0] * (N + 1) fac[0] = 1 for i in range(N): fac[i + 1] = fac[i] * (i + 1) % m def mcomb(n, k): if n == 0 and k == 0: return 1 if n < k or k < 0: return 0 return fac[n] * pow(fac[n - k], m - 2, m) * pow(fac[k], m - 2, m) % m A.sort(reverse=True) result = 0 for i in range(N - K + 1): result += A[i] * mcomb(N - (i + 1), K - 1) result %= m A.sort() t = 0 for i in range(N - K + 1): t += A[i] * mcomb(N - (i + 1), K - 1) t %= m result -= t result %= m print(result)
p02804
# -*- coding: utf-8 -*- class FactMod(): ''' modの値が素数の時のfactと組み合わせを求める フェルマーの小定理を用いているため、modが素数以外の時は使えない ''' def __init__(self, n, mod): ''' コンストラクタ f:nまでの i!の値を 配列に入れる inv: (i!)^-1 の値を配列に入れる ''' self.mod = mod self.f = [1]*(n+1) for i in range(1, n+1): self.f[i] = self.f[i-1]*i % mod self.inv = [pow(self.f[-1], mod-2, mod)] for i in range(1, n+1)[::-1]: self.inv.append(self.inv[-1]*i % mod) self.inv.reverse() def fact(self, n): ''' n!の値を返す ''' return self.f[n] def comb(self, n, r): ''' nCrの値を返す ''' ret = self.f[n] * self.inv[n-r]*self.inv[r] ret %= self.mod return ret def perm(self, n, r): """ nPrの値を返す """ ret = self.f[n] * self.inv[n-r] ret %= self.mod return ret N, K = list(map(int, input().split())) L = list(map(int, input().split())) L = sorted(L) MOD = 10**9+7 F = FactMod(N+1, MOD) sub = 0 add = 0 for i in reversed(list(range(K-1, N))): add += L[i]*F.comb(i, K-1) sub += L[N-i-1]*F.comb(i, K-1) print(((-sub+add+MOD) % MOD))
# -*- coding: utf-8 -*- class FactMod(): ''' modの値が素数の時のfactと組み合わせを求める フェルマーの小定理を用いているため、modが素数以外の時は使えない ''' def __init__(self, n, mod): ''' コンストラクタ f:nまでの i!の値を 配列に入れる inv: (i!)^-1 の値を配列に入れる ''' self.mod = mod self.f = [1]*(n+1) for i in range(1, n+1): self.f[i] = self.f[i-1]*i % mod self.inv = [pow(self.f[-1], mod-2, mod)] for i in range(1, n+1)[::-1]: self.inv.append(self.inv[-1]*i % mod) self.inv.reverse() def fact(self, n): ''' n!の値を返す ''' return self.f[n] def comb(self, n, r): ''' nCrの値を返す ''' ret = self.f[n] * self.inv[n-r]*self.inv[r] ret %= self.mod return ret def perm(self, n, r): """ nPrの値を返す """ ret = self.f[n] * self.inv[n-r] ret %= self.mod return ret N, K = list(map(int, input().split())) L = list(map(int, input().split())) L = sorted(L) MOD = 10**9+7 F = FactMod(N+1, MOD) print((sum([(L[i]-L[N-i-1]+MOD)*F.comb(i, K-1) % MOD for i in reversed(list(range(K-1, N)))]) % MOD))
p02804
# 組み合わせ(高速,フェルマーの小定理を利用) def cmb(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 #出力の制限 N = 10 ** 5 g1 = [1, 1] # 元テーブル g2 = [1, 1] #逆元テーブル inverse = [0, 1] #逆元テーブル計算用テーブル for i in range( 2, N + 1 ): g1.append( ( g1[-1] * i ) % mod ) inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod ) g2.append( (g2[-1] * inverse[-1]) % mod ) mod = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() ans = 0 for i in range(N-K+1): now_A = A[i] tmp = 1 count = 0 for k in range(i+K-1, N): ans += cmb(K-2+count, count, mod) * (A[k] - now_A) ans %= mod count += 1 print((ans%mod))
# 組み合わせ(高速,フェルマーの小定理を利用) def cmb(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 10**9+7 #出力の制限 N = 10 ** 5 g1 = [1, 1] # 元テーブル g2 = [1, 1] #逆元テーブル inverse = [0, 1] #逆元テーブル計算用テーブル for i in range( 2, N + 1 ): g1.append( ( g1[-1] * i ) % mod ) inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod ) g2.append( (g2[-1] * inverse[-1]) % mod ) mod = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() ans_max = 0 ans_min = 0 # ans_minを求める for i in range(N-K+1): ans_min += A[i] * cmb(N-1-i, K-1, mod) ans_min %= mod for i in range(K-1, N): ans_max += A[i] * cmb(i, K-1, mod) ans_max %= mod ##print(ans_max, ans_min) print(((ans_max - ans_min + mod)%mod))
p02804
P = 10**9 + 7 N = 1000000 inv_t = [0]+[1] for i in range(2,N): inv_t += [inv_t[P % i] * (P - int(P / i)) % P] n, k = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10 ** 9 + 7 A.sort() mini_count = 0 maxim_count = 0 pattern = 1 for i in range(n-k, -1, -1): mini = A[i] mini_count += mini * pattern % mod mini_count %= mod pattern = pattern * (n-i) * inv_t[n-i-k+1] % mod pattern = 1 for i in range(n-k+1, 0, -1): maxim = A[-i] maxim_count += maxim * pattern % mod maxim_count %= mod pattern = pattern * (n-i+1) * inv_t[n-i-k+2] % mod ans = maxim_count - mini_count ans %= mod print(ans)
P = 10**9 + 7 N = 200000 inv_t = [0]+[1] # 逆元 for i in range(2, N): inv_t += [inv_t[P % i] * (P - int(P / i)) % P] n, k = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10 ** 9 + 7 A.sort() mini_count = 0 maxim_count = 0 pattern = 1 """ minX, maxXとして選ばれるのはそれぞれ minX:sortAの右からk番目(大きい数値からk個取った時の最小値)とそれより左の要素 maxX:sortAの左からk番目(小さい数値からk個取った時の最大値)とそれより右の要素 選ばれるパターンはminXの場合自分の要素より右にある要素からk-1個を選ぶパターン数 つまり最初は(k-1)C(k-1) = 1 選べる要素が一つ増えるごとに tC(k-1) ⇒ (t+1)C(k-1)のように増えるので t * t-1 * t-2 ... * t-k ⇒ t+1 * t * t-1 ... * t-k+1 であり つまりパターン数は (t+1) / (t-k) 倍になる """ for idx in range(k, n + 1): mini = A[-idx] # mini_count += mini * pattern % mod mini_count %= mod maxim = A[idx - 1] maxim_count += maxim * pattern % mod maxim_count %= mod pattern = pattern * (idx) * inv_t[idx + 1 - k] % mod # 割り算のmodは逆元をかける ans = maxim_count - mini_count ans %= mod print(ans)
p02804
P = 10**9 + 7 N = 200000 inv_t = [0]+[1] # 逆元 for i in range(2, N): inv_t += [inv_t[P % i] * (P - int(P / i)) % P] n, k = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10 ** 9 + 7 A.sort() mini_count = 0 maxim_count = 0 pattern = 1 """ minX, maxXとして選ばれるのはそれぞれ minX:sortAの右からk番目(大きい数値からk個取った時の最小値)とそれより左の要素 maxX:sortAの左からk番目(小さい数値からk個取った時の最大値)とそれより右の要素 選ばれるパターンはminXの場合自分の要素より右にある要素からk-1個を選ぶパターン数 つまり最初は(k-1)C(k-1) = 1 選べる要素が一つ増えるごとに tC(k-1) ⇒ (t+1)C(k-1)のように増えるので t * t-1 * t-2 ... * t-k ⇒ t+1 * t * t-1 ... * t-k+1 であり つまりパターン数は (t+1) / (t-k) 倍になる """ for idx in range(k, n + 1): mini = A[-idx] # mini_count += mini * pattern % mod mini_count %= mod maxim = A[idx - 1] maxim_count += maxim * pattern % mod maxim_count %= mod pattern = pattern * (idx) * inv_t[idx + 1 - k] % mod # 割り算のmodは逆元をかける ans = maxim_count - mini_count ans %= mod print(ans)
n, k = list(map(int, input().split())) A = list(map(int, input().split())) mod = 10 ** 9 + 7 P = 10**9 + 7 N = n-k+10 inv_t = [0]+[1] # 逆元 for i in range(2, N): inv_t += [inv_t[P % i] * (P - int(P / i)) % P] A.sort() mini_count = 0 maxim_count = 0 pattern = 1 """ minX, maxXとして選ばれるのはそれぞれ minX:sortAの右からk番目(大きい数値からk個取った時の最小値)とそれより左の要素 maxX:sortAの左からk番目(小さい数値からk個取った時の最大値)とそれより右の要素 選ばれるパターンはminXの場合自分の要素より右にある要素からk-1個を選ぶパターン数 つまり最初は(k-1)C(k-1) = 1 選べる要素が一つ増えるごとに tC(k-1) ⇒ (t+1)C(k-1)のように増えるので t * t-1 * t-2 ... * t-k ⇒ t+1 * t * t-1 ... * t-k+1 であり つまりパターン数は (t+1) / (t-k) 倍になる """ for idx in range(k, n + 1): mini = A[-idx] # mini_count += mini * pattern % mod mini_count %= mod maxim = A[idx - 1] maxim_count += maxim * pattern % mod maxim_count %= mod pattern = pattern * (idx) * inv_t[idx + 1 - k] % mod # 割り算のmodは逆元をかける ans = maxim_count - mini_count ans %= mod print(ans)
p02804
class BinomialCoefficient(object): def __init__(self, N=510000, MOD=10**9+7): self.fac = [1, 1] self.finv = [1, 1] self.inv = [0, 1] self.MOD = MOD for i in range(2, N + 1): self.fac.append((self.fac[-1] * i) % MOD) self.inv.append((-self.inv[MOD % i] * (MOD // i)) % MOD) self.finv.append((self.finv[-1] * self.inv[-1]) % MOD) def comb(self, n, r): if r < 0 or n < r or r < 0: return 0 return self.fac[n] * self.finv[r] * self.finv[n - r] % self.MOD N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10 ** 9 + 7 A.sort() bc = BinomialCoefficient() nCk = bc.comb(N, K) ans = 0 for i in range(N - 1): c = nCk - bc.comb(i + 1, K) - bc.comb((N - i - 1), K) ans += c * (A[i + 1] - A[i]) % MOD ans %= MOD print(ans)
class BinomialCoefficient(object): def __init__(self, N=510000, MOD=10**9+7): self.fac = [1, 1] self.finv = [1, 1] self.inv = [0, 1] self.MOD = MOD for i in range(2, N + 1): self.fac.append((self.fac[-1] * i) % MOD) self.inv.append((-self.inv[MOD % i] * (MOD // i)) % MOD) self.finv.append((self.finv[-1] * self.inv[-1]) % MOD) def comb(self, n, r): if r < 0 or n < r or r < 0: return 0 return self.fac[n] * self.finv[r] * self.finv[n - r] % self.MOD N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10 ** 9 + 7 A.sort() bc = BinomialCoefficient(N) nCk = bc.comb(N, K) ans = 0 for i in range(N - 1): c = nCk - bc.comb(i + 1, K) - bc.comb((N - i - 1), K) ans += c * (A[i + 1] - A[i]) % MOD ans %= MOD print(ans)
p02804
from bisect import bisect_right, bisect_left class Combination: def __init__(self, size, mod=10**9 + 7): self.size = size + 2 self.mod = mod self.fact = [1, 1] + [0] * size self.factInv = [1, 1] + [0] * size self.inv = [0, 1] + [0] * size for i in range(2, self.size): self.fact[i] = self.fact[i - 1] * i % self.mod self.inv[i] = -self.inv[self.mod % i] * (self.mod // i) % self.mod self.factInv[i] = self.factInv[i - 1] * self.inv[i] % self.mod def npr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * self.factInv[n - r] % self.mod def ncr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * (self.factInv[r] * self.factInv[n - r] % self.mod) % self.mod def nhr(self, n, r): # 重複組合せ return self.ncr(n + r - 1, n - 1) def factN(self, n): if n < 0: return 0 return self.fact[n] N, K = list(map(int, input().split())) MOD = 10**9 + 7 comb = Combination(N + 100) A = list(map(int, input().split())) A.sort() ans = 0 for i, a in enumerate(A): mi = min(i, bisect_right(A, a) - 1) mx = N - max(i + 1, bisect_left(A, a)) ans = (ans + (comb.ncr(mi, K - 1) - comb.ncr(mx, K - 1)) * a) % MOD print(ans)
MOD = 10**9 + 7 class Combination: def __init__(self, size): self.size = size + 2 self.fact = [1, 1] + [0] * size self.factInv = [1, 1] + [0] * size self.inv = [0, 1] + [0] * size for i in range(2, self.size): self.fact[i] = self.fact[i - 1] * i % MOD self.inv[i] = -self.inv[MOD % i] * (MOD // i) % MOD self.factInv[i] = self.factInv[i - 1] * self.inv[i] % MOD def npr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * self.factInv[n - r] % MOD def ncr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * (self.factInv[r] * self.factInv[n - r] % MOD) % MOD def nhr(self, n, r): # 重複組合せ: x_1 + ... + x_n = r return self.ncr(n + r - 1, n - 1) N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10**9 + 7 comb = Combination(N + 10) A.sort() ans = 0 for i, a in enumerate(A): mi = comb.ncr(N - i - 1, K - 1) mx = comb.ncr(i, K - 1) ans += (mx - mi) * a ans %= MOD print(ans)
p02804
MOD = 10**9 + 7 class Combination: def __init__(self, size): self.size = size + 2 self.fact = [1, 1] + [0] * size self.factInv = [1, 1] + [0] * size self.inv = [0, 1] + [0] * size for i in range(2, self.size): self.fact[i] = self.fact[i - 1] * i % MOD self.inv[i] = -self.inv[MOD % i] * (MOD // i) % MOD self.factInv[i] = self.factInv[i - 1] * self.inv[i] % MOD def npr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * self.factInv[n - r] % MOD def ncr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * (self.factInv[r] * self.factInv[n - r] % MOD) % MOD def nhr(self, n, r): # 重複組合せ: x_1 + ... + x_n = r return self.ncr(n + r - 1, n - 1) N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10**9 + 7 comb = Combination(N + 10) A.sort() ans = 0 for i, a in enumerate(A): mi = comb.ncr(N - i - 1, K - 1) mx = comb.ncr(i, K - 1) ans += (mx - mi) * a ans %= MOD print(ans)
MOD = 10**9 + 7 class Combination: def __init__(self, size): self.size = size + 2 self.fact = [1, 1] + [0] * size self.factInv = [1, 1] + [0] * size self.inv = [0, 1] + [0] * size for i in range(2, self.size): self.fact[i] = self.fact[i - 1] * i % MOD self.inv[i] = -self.inv[MOD % i] * (MOD // i) % MOD self.factInv[i] = self.factInv[i - 1] * self.inv[i] % MOD def npr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * self.factInv[n - r] % MOD def ncr(self, n, r): if n < r or n < 0 or r < 0: return 0 return self.fact[n] * (self.factInv[r] * self.factInv[n - r] % MOD) % MOD def nhr(self, n, r): # 重複組合せ: x_1 + ... + x_n = r return self.ncr(n + r - 1, n - 1) N, K = list(map(int, input().split())) A = list(map(int, input().split())) comb = Combination(N + 100) A.sort() ans = 0 for i, a in enumerate(A): ans += a * comb.ncr(i, K - 1) ans -= a * comb.ncr(N - i - 1, K - 1) ans %= MOD print(ans)
p02804
def comb(a,b,m): if b == 0 or b == a: ret = 1 else: ret = 1 for i in range(a-b+1,a+1): ret = (ret * i) % m for i in range(1,b+1): ret = (ret * pow(i,m-2,m) ) % m return ret mod = 10**9+7 n, k = [ int(v) for v in input().split() ] num = sorted([ int(v) for v in input().split() ]) max_list2 = [ (i, i-k+1) for i in range(n) ] max_list2 = [ comb(a, b, mod) if b >= 0 else 0 for a, b in max_list2 ] min_list_2 = list(reversed(max_list2)) max_min_list = [ (max_list2[i] - min_list_2[i]) * num[i] for i in range(n) ] print((sum(max_min_list) % mod))
mod = 10**9+7 n, k = [ int(v) for v in input().split() ] num = sorted([ int(v) for v in input().split() ]) max_list2 = [ (i, i-k+1) for i in range(n) ] max_list = [] for a, b in max_list2: if b < 0: max_list.append(0) elif b == 0: max_list.append(1) else: s = max_list[-1] s *= a * pow(b, mod-2, mod) max_list.append(s%mod) min_list = list(reversed(max_list)) max_min_list = [ (max_list[i] - min_list[i]) * num[i] for i in range(n) ] print((sum(max_min_list) % mod))
p02804
from math import factorial N,K=list(map(int,input().split())) A=list(map(int,input().split())) mod = 10**9+7 if K==1:print((0)) else: def comb(n,k): return factorial(n)*pow(factorial(n-k)*factorial(k), -1, mod) A1=sorted(A) A2=A1[::-1] ans=0 for i in range(N-K+1): ans += (A2[i]-A1[i])*comb(N-i-1,K-1) ans %= mod print(ans)
N,K=list(map(int,input().split())) A=list(map(int,input().split())) mod = 10**9+7 if K==1:print((0)) else: factorial=[1 for i in range(N+1)] for i in range(1,N+1): if i==1:factorial[i]=1 else:factorial[i] = factorial[i-1]*i % mod def comb(n,k): return factorial[n]*pow(factorial[n-k]*factorial[k], -1, mod) A1=sorted(A) A2=A1[::-1] ans=0 for i in range(N-K+1): ans += (A2[i]-A1[i])*comb(N-i-1,K-1) ans %= mod print(ans)
p02804
N, K = list(map(int,input().split())) A = list(map(int,input().split())) MAX = 10 ** 5 + 1 MOD = 10 ** 9 + 7 fac = [0] * (MAX + 1) fac[0] = 1 fac[1] = 1 for i in range(2, MAX + 1): fac[i] = fac[i - 1] * i % MOD finv = [0] * (MAX + 1) finv[MAX] = pow(fac[MAX], MOD - 2, MOD) for i in range(MAX, 0, -1): finv[i - 1] = finv[i] * i % MOD def comb(n, k): if n < k or k < 0: return 0 return (fac[n] * finv[k] * finv[n - k]) % MOD A.sort() ans = 0 for i in range(N): if i >= K - 1: ans += comb(i, K - 1) * A[i] if i + K - 1 < N: ans -= comb(N - i - 1, K - 1) * A[i] ans %= MOD print(ans)
N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() MAX = 10 ** 5 + 1 MOD = 10 ** 9 + 7 fac = [0]*(MAX+1) fac[0] = 1 fac[1] = 1 for i in range(2,MAX+1): fac[i] = fac[i-1]*i%MOD finv = [0]*(MAX+1) finv[MAX] = pow(fac[MAX], MOD-2, MOD) for i in range(MAX, 0, -1): finv[i-1] = finv[i] * i % MOD def comb(n, k): if n < k or k < 0: return 0 return (fac[n] * finv[k] * finv[n - k]) % MOD ans = 0 for i in range(N): if K - 1 <= i: ans += comb(i,K-1) * A[i] if K-1+i < N: ans -= comb(N-i-1,K-1)*A[i] ans %= MOD print(ans)
p02804
def power(a,n): x=1 L=list(format(n,'b')) l=len(L) for i in range(l): if int(L[l-i-1])==1: x=(x*a)%(10**9+7) a=(a*a)%(10**9+7) return x N,K=list(map(int,input().split())) A=list(map(int,input().split())) b=sorted(A) c=sorted(A,reverse=True) D=[] M=0 for i in range(N-K+1): x=1 y=1 for l in range(K-1): x=(x*(N-i-1-l))%(10**9+7) y=(y*(l+1))%(10**9+7) y=power(y,10**9+5) m=(x*y*(c[i]-b[i])) if m>0: m=m%(10**9+7) M+=m M%(10**9+7) print((M%(10**9+7)))
def power(a,n): x=1 L=list(format(n,'b')) l=len(L) for i in range(l): if int(L[l-i-1])==1: x=(x*a)%(10**9+7) a=(a*a)%(10**9+7) return x N,K=list(map(int,input().split())) A=list(map(int,input().split())) b=sorted(A) c=sorted(A,reverse=True) D=[] M=0 x=1 y=1 for l in range(K-1): x=(x*(N-l-1))%(10**9+7) y=(y*(l+1))%(10**9+7) y=power(y,10**9+5) M+=(x*y*(c[0]-b[0]))%(10**9+7) for i in range(1,N-K+1): y1=power(N-i,10**9+5) x=(x*y1)%(10**9+7) x=(x*(N-K-i+1))%(10**9+7) m=(x*y*(c[i]-b[i])) if m>0: m=m%(10**9+7) M+=m M%(10**9+7) print((M%(10**9+7)))
p02804
def cmb(n,r,mod): a=1 b=1 r = min(r,n-r) for i in range(r): a = a*(n-i)%mod b = b*(i+1)%mod return a*pow(b,mod-2,mod)%mod N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() mod = 10**9+7 ans = 0 if K == 1: print((0)) else: for i in range(0,N-K+1): ans -= A[i]*cmb(N-i-1,K-1,10**9+7) for i in range(K-1,N): ans += A[i]*cmb(i,K-1,10**9+7) print((ans%mod))
# kurimu_usamaro様のメソッドを拝借しています。 class Combi(): def __init__(self, N, mod): self.power = [1 for _ in range(N+1)] self.rev = [1 for _ in range(N+1)] self.mod = mod for i in range(2, N+1): self.power[i] = (self.power[i-1]*i) % self.mod self.rev[N] = pow(self.power[N], self.mod-2, self.mod) for j in range(N, 0, -1): self.rev[j-1] = (self.rev[j]*j) % self.mod def com(self, K, R): if K < R: return 0 else: return ((self.power[K])*(self.rev[K-R])*(self.rev[R])) % self.mod def pom(self, K, R): if K < R: return 0 else: return (self.power[K])*(self.rev[K-R]) % self.mod def main(): mod = 10**9+7 N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() c = Combi(N,mod) ans = 0 if K == 1: print((0)) else: for i, a in enumerate(A): ans += c.com(i, K-1)*a ans -= c.com(N-1-i, K-1)*a ans %= mod print((ans%mod)) if __name__ == "__main__": main()
p02804
def COMint(): fac[0]=1 fac[1]=1 finv[0]=1 finv[1]=1 inv[1]=1 for i in range(2,N+1): fac[i] = fac[i - 1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i - 1] * inv[i] % MOD def com(n,k): return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD MOD=10**9+7 N,K=[int(x) for x in input().split()] A= [int(x) for x in input().split()] A= sorted(A) fac=[0]*(N+1) inv=[0]*(N+1) finv=[0]*(N+1) COMint() ans=0 #print(fac) for j in range(N-1,-1,-1): for i in range(j-K+2): mi = A[i] ma = A[j] #print(ma,mi,i,j,L[j-i-1]) # print(j-i-1,com(j-i-1,K-2)) ans+=(ma-mi)*com(j-i-1,K-2) print((ans%(10**9+7)))
def COMint(): fac[0]=1 fac[1]=1 finv[0]=1 finv[1]=1 inv[1]=1 for i in range(2,N+1): fac[i] = fac[i - 1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i - 1] * inv[i] % MOD def com(n,k): if n<k: return 0 return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD MOD=10**9+7 N,K=[int(x) for x in input().split()] A= [int(x) for x in input().split()] A= sorted(A) fac=[0]*(N+1) inv=[0]*(N+1) finv=[0]*(N+1) COMint() ans=0 #print(fac) for j in range(N): ans+=(A[j])*com(j,K-1) ans-=(A[j])*com(N-1-j,K-1) print((ans%(10**9+7)))
p02804
MOD = 10**9+7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort(reverse=True) f = [1] for i in range(10**5+7): f.append(f[-1]*(i+1)%MOD) def nCr(n, r, mod=MOD): return f[n] * pow(f[r], mod-2, mod) * pow(f[n-r], mod-2, mod) % mod ans = 0 for i in range(N-K+1): ans += (A[i] - A[-1-i]) * nCr(N-1-i, K-1) ans %= MOD print(ans)
MOD = 10**9+7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() f = [1] for i in range(10**5): f.append(f[-1] * (i+1) % MOD) def nCr(n, r, mod=MOD): return f[n] * pow(f[r], mod-2, mod) * pow(f[n-r], mod-2, mod) % mod ans = 0 for i in range(N-K+1): ans -= (A[i] - A[-1-i]) * nCr(N-1-i, K-1) ans %= MOD print(ans)
p02804
MOD = 10**9+7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() f = [1] for i in range(10**5): f.append(f[-1] * (i+1) % MOD) def nCr(n, r, mod=MOD): return f[n] * pow(f[r], mod-2, mod) * pow(f[n-r], mod-2, mod) % mod ans = 0 for i in range(N-K+1): ans += (A[-1-i] - A[i]) * nCr(N-1-i, K-1) ans %= MOD print(ans)
import sys readline = sys.stdin.buffer.readline MOD = 10**9+7 N, K = list(map(int, readline().split())) A = list(map(int, readline().split())) A.sort() f = [1] for i in range(10**5): f.append(f[-1] * (i+1) % MOD) def nCr(n, r, mod=MOD): return f[n] * pow(f[r], mod-2, mod) * pow(f[n-r], mod-2, mod) % mod ans = 0 for i in range(N-K+1): ans += (A[-1-i] - A[i]) * nCr(N-1-i, K-1) ans %= MOD print(ans)
p02804
import sys read = sys.stdin.buffer.read input = sys.stdin.buffer.readline inputs = sys.stdin.buffer.readlines mod=10**9+7 # rstrip().decode('utf-8') # map(int,input().split()) #import numpy as np def framod(n, mod, a=1): for i in range(1,n+1): a=a * i % mod return a def power(n, r, mod): if r == 0: return 1 if r%2 == 0: return power(n*n % mod, r//2, mod) % mod if r%2 == 1: return n * power(n, r-1, mod) % mod def comb(n, k, mod): a=framod(n, mod) b=framod(k, mod) c=framod(n-k, mod) return (a * power(b, mod-2, mod) * power(c, mod-2, mod)) % mod def main(): n,k=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() ans=0 for i in range(n-k+1): ans+=((comb(k-1+i,k-1,mod)*A[k-1+i])-(comb(k-1+i,k-1,mod)*A[n-k-i]))%mod ans=ans%mod print(ans) if __name__ == "__main__": main()
import sys read = sys.stdin.buffer.read input = sys.stdin.buffer.readline inputs = sys.stdin.buffer.readlines mod=10**9+7 # rstrip().decode('utf-8') # map(int,input().split()) #import numpy as np def power(n, r, mod): if r == 0: return 1 if r%2 == 0: return power(n*n % mod, r//2, mod) % mod if r%2 == 1: return n * power(n, r-1, mod) % mod def main(): n,k=list(map(int,input().split())) A=list(map(int,input().split())) A.sort() comb=[1] for i in range(n-k): comb.append((comb[-1]*(k+i)*pow(i+1,mod-2,mod))%mod) ans=0 for i in range(n-k+1): ans+=((comb[i]*A[k-1+i])-(comb[i]*A[n-k-i]))%mod ans=ans%mod print(ans) if __name__ == "__main__": main()
p02804
n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort() mod=10**9+7 def modfc(x,y,p): f=1 for i in range(x,y+1): f=f%p*i%p return f%p def comb(x,y,p): return modfc(x-y+1,x,p)*pow(modfc(1,y,p),p-2,p) maxs=0 for i in range(k,n+1): maxs+=a[i-1]*comb(i-1,k-1,mod) maxs%=mod mins=0 for i in range(n-k+1): mins+=a[i]*comb(n-i-1,k-1,mod) mins%=mod ans=(maxs-mins)%mod print((ans+mod if ans<0 else ans))
n,k=list(map(int,input().split())) a=list(map(int,input().split())) a.sort() mod=10**9+7 fcl=[1]*(n+1) for i in range(1,n+1): fcl[i]=(fcl[i-1]*i)%mod def comb(x,y,p): return ((fcl[x]*pow(fcl[y],p-2,p))%mod*pow(fcl[x-y],p-2,p))%mod maxs=0 for i in range(k,n+1): maxs+=a[i-1]*comb(i-1,k-1,mod) maxs%=mod mins=0 for i in range(n-k+1): mins+=a[i]*comb(n-i-1,k-1,mod) mins%=mod ans=(maxs-mins)%mod print((ans+mod if ans<0 else ans))
p02804
N_MAX = 10**6 MOD = 10**9 + 7 fac, finv, inv = [0]*N_MAX ,[0]*N_MAX, [0]*N_MAX def com_init(): fac[0], fac[1] = 1, 1 finv[0], finv[1] = 1, 1 inv[1] = 1 for i in range(2, N_MAX): fac[i] = fac[i - 1] * i % MOD inv[i] = MOD - inv[MOD%i] * (MOD // i) % MOD finv[i] = finv[i - 1] * inv[i] % MOD def com(n, k): if n < k: return 0 if n < 0 or k < 0: return 0 return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD n,k = list(map(int, input().split())) al = list(map(int, input().split())) com_init() al.sort() ans_max = 0 ans_min = 0 for i,a in enumerate(al): ans_max += a*com(i,k-1) ans_max%=MOD ans_min += a*com(n-1-i,k-1) ans_min%=MOD print(((ans_max-ans_min)%MOD))
class Combination: def __init__(self, n_max=10**6, mod=10**9+7): # self._n_max = n_max self._fac, self._finv, self._inv = [0]*n_max, [0]*n_max, [0]*n_max self._fac[0], self._fac[1] = 1, 1 self._finv[0], self._finv[1] = 1, 1 self._inv[1] = 1 for i in range(2, n_max): self._fac[i] = self._fac[i - 1] * i % MOD self._inv[i] = MOD - self._inv[MOD%i] * (MOD // i) % MOD self._finv[i] = self._finv[i - 1] * self._inv[i] % MOD def com(self, n, r): if n < r: return 0 if n < 0 or r < 0: return 0 return self._fac[n] * (self._finv[r] * self._finv[n - r] % MOD) % MOD MOD = 10**9+7 # comb.com(10,3) comb = Combination(10**5+1, MOD) n,k = list(map(int, input().split())) al=list(map(int, input().split())) al.sort(reverse=True) fmax = 0 for i,a in enumerate(al): cnt = comb.com(n-i-1,k-1) fmax += cnt*a fmax%=MOD al.sort() fmin = 0 for i,a in enumerate(al): cnt = comb.com(n-i-1,k-1) fmin += cnt*a fmin%=MOD ans = fmax-fmin ans%=MOD print(ans)
p02804
class Combinatorics: def __init__(self, N, mod): ''' Preprocess for calculating binomial coefficients nCr (0 <= r <= n, 0 <= n <= N) over the finite field Z/(mod)Z. Input: N (int): maximum n mod (int): a prime number. The order of the field Z/(mod)Z over which nCr is calculated. ''' self.mod = mod self.fact = {i: None for i in range(N+1)} # n! self.inverse = {i: None for i in range(1, N+1)} # inverse of n in the field Z/(MOD)Z self.fact_inverse = {i: None for i in range(N+1)} # inverse of n! in the field Z/(MOD)Z # preprocess self.fact[0] = self.fact[1] = 1 self.fact_inverse[0] = self.fact_inverse[1] = 1 self.inverse[1] = 1 for i in range(2, N+1): self.fact[i] = i * self.fact[i-1] % self.mod q, r = divmod(self.mod, i) self.inverse[i] = (- (q % self.mod) * self.inverse[r]) % self.mod self.fact_inverse[i] = self.inverse[i] * self.fact_inverse[i-1] % self.mod def perm(self, n, r): ''' Calculate nPr = n! / (n-r)! % mod ''' if n < r or n < 0 or r < 0: return 0 else: return (self.fact[n] * self.fact_inverse[n-r]) % self.mod def binom(self, n, r): ''' Calculate nCr = n! /(r! (n-r)!) % mod ''' if n < r or n < 0 or r < 0: return 0 else: return self.fact[n] * (self.fact_inverse[r] * self.fact_inverse[n-r] % self.mod) % self.mod def hom(self, n, r): ''' Calculate nHr = {n+r-1}Cr % mod. Assign r objects to one of n classes. Arrangement of r circles and n-1 partitions: o o o | o o | | | o | | | o o | | o ''' if n == 0 and r > 0: return 0 if n >= 0 and r == 0: return 1 return self.binom(n + r - 1, r) MOD = 10**9 + 7 N, K = list(map(int, input().split())) *A, = list(map(int, input().split())) if K == 1: print((0)) else: A = sorted(A) com = Combinatorics(N, MOD) ans = 0 for i in range(N-K+1): min_S = A[i] for j in range(i+K-1, N): max_S = A[j] ans += (max_S - min_S) * com.binom(j - i - 1, K - 2) ans %= MOD print(ans)
class Combinatorics: def __init__(self, N, mod): ''' Preprocess for calculating binomial coefficients nCr (0 <= r <= n, 0 <= n <= N) over the finite field Z/(mod)Z. Input: N (int): maximum n mod (int): a prime number. The order of the field Z/(mod)Z over which nCr is calculated. ''' self.mod = mod self.fact = {i: None for i in range(N+1)} # n! self.inverse = {i: None for i in range(1, N+1)} # inverse of n in the field Z/(MOD)Z self.fact_inverse = {i: None for i in range(N+1)} # inverse of n! in the field Z/(MOD)Z # preprocess self.fact[0] = self.fact[1] = 1 self.fact_inverse[0] = self.fact_inverse[1] = 1 self.inverse[1] = 1 for i in range(2, N+1): self.fact[i] = i * self.fact[i-1] % self.mod q, r = divmod(self.mod, i) self.inverse[i] = (- (q % self.mod) * self.inverse[r]) % self.mod self.fact_inverse[i] = self.inverse[i] * self.fact_inverse[i-1] % self.mod def perm(self, n, r): ''' Calculate nPr = n! / (n-r)! % mod ''' if n < r or n < 0 or r < 0: return 0 else: return (self.fact[n] * self.fact_inverse[n-r]) % self.mod def binom(self, n, r): ''' Calculate nCr = n! /(r! (n-r)!) % mod ''' if n < r or n < 0 or r < 0: return 0 else: return self.fact[n] * (self.fact_inverse[r] * self.fact_inverse[n-r] % self.mod) % self.mod def hom(self, n, r): ''' Calculate nHr = {n+r-1}Cr % mod. Assign r objects to one of n classes. Arrangement of r circles and n-1 partitions: o o o | o o | | | o | | | o o | | o ''' if n == 0 and r > 0: return 0 if n >= 0 and r == 0: return 1 return self.binom(n + r - 1, r) MOD = 10**9 + 7 N, K = list(map(int, input().split())) *A, = list(map(int, input().split())) A = sorted(A) com = Combinatorics(N, MOD) ans = 0 for i, a in enumerate(A): ans = (ans + a * com.binom(i, K-1)) % MOD ans = (ans - a * com.binom(N-i-1, K-1)) % MOD print(ans)
p02804
N, K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() MOD = 10**9+7 fac = [0]*(N+1) # 階乗テーブル fac[0] = fac[1] = 1 inv = [0]*(N+1) # 逆元テーブル inv[1] = 1 facinv = [0]*(N+1) # 階乗の逆元テーブル facinv[0] = facinv[1] = 1 for i in range(2,N+1): fac[i] = fac[i-1]*i%MOD inv[i] = MOD - inv[MOD%i] * (MOD//i) % MOD facinv[i] = facinv[i-1] * inv[i] % MOD def nCr(n,r): if n < r or n < 0 or r < 0:return 0 else:return fac[n] * (facinv[r] * facinv[n-r] % MOD) % MOD # 各要素が最大値、最小値として何回使われるか考える maxsum = 0 minsum = 0 for i,a in enumerate(A): maxsum += nCr(i,K-1)*a maxsum %= MOD minsum += nCr(N-i-1,K-1)*a minsum %= MOD ans = (maxsum-minsum)%MOD print(ans)
N,K = list(map(int,input().split())) A = list(map(int,input().split())) A.sort() MOD = 10**9+7 # 各aが何回最大最小として選ばれるか考える ans = 0 class Combination: def __init__(self, n_max, mod=10**9+7): self.mod = mod self.modinv = self.make_modinv_list(n_max) self.fac, self.facinv = self.make_factorial_list(n_max) def __call__(self, n, r): return self.fac[n] * self.facinv[r] % self.mod * self.facinv[n-r] % self.mod def make_factorial_list(self, n): # 階乗のリストと階乗のmod逆元のリストを返す O(n) # self.make_modinv_list()が先に実行されている必要がある fac = [1] facinv = [1] for i in range(1, n+1): fac.append(fac[i-1] * i % self.mod) facinv.append(facinv[i-1] * self.modinv[i] % self.mod) return fac, facinv def make_modinv_list(self, n): # 0からnまでのmod逆元のリストを返す O(n) modinv = [0] * (n+1) modinv[1] = 1 for i in range(2, n+1): modinv[i] = self.mod - self.mod//i * modinv[self.mod%i] % self.mod return modinv comb = Combination(N+1) for i in range(N): if i >= K-1: ans += (A[i] * comb(i,K-1))%MOD ans %= MOD for i in range(N): if i <= N-K: ans -= (A[i] * comb(N-1-i,K-1))%MOD ans %= MOD print(ans)
p02804
N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10 ** 9 + 7 kai = [1] for i in range(1, N + 1): kai.append(kai[-1] * i) def comb(n, r): return kai[n] // (kai[n - r] * kai[r]) if K >= 2: A.sort(reverse = True) ans = 0 for i in range(N - K + 1): for j in range(i + K - 1, N): ans += (A[i] - A[j]) * comb(j - i - 1, max(0, K - 2)) ans %= MOD print(ans) else: print((0))
N, K = list(map(int, input().split())) A = list(map(int, input().split())) MOD = 10 ** 9 + 7 kai1 = [1, 1] kai2 = [1, 1] inverse = [0, 1] for i in range(2, N + 1): kai1.append((kai1[-1] * i) % MOD) inverse.append((-inverse[MOD % i] * (MOD // i)) % MOD) kai2.append((kai2[-1] * inverse[-1]) % MOD) def comb(n, r): if r < 0 or r > n: return 0 r = min(r, n - r) return (kai1[n] * kai2[r] * kai2[n - r]) % MOD if K >= 2: A.sort(reverse = True) ans = 0 for i in range(N - K + 1): for j in range(i + K - 1, N): ans += (A[i] - A[j]) * comb(j - i - 1, max(0, K - 2)) ans %= MOD print(ans) else: print((0))
p02804
n, k = list(map(int, input().split())) a = list(map(int, input().split())) a.sort() a2 = [] for i, x in enumerate(a): a2.append((x, i)) from math import factorial def c(n, r): if n - r < 0: return 0 return factorial(n) // factorial(r) // factorial(n - r) ma = 0 mi = 0 for i in range(n): ma += a[i] * c(i, k - 1) mi += a[i] * c(n - i - 1, k - 1) MOD = 10**9 + 7 print(((ma - mi) % MOD))
n, k = list(map(int, input().split())) a = list(map(int, input().split())) a.sort() a2 = [] for i, x in enumerate(a): a2.append((x, i)) from math import factorial def c(n, r): if n - r < 0: return 0 return factorial(n) // factorial(r) // factorial(n - r) MOD = 10**9 + 7 # 出力の制限 # https://qiita.com/derodero24/items/91b6468e66923a87f39f def cmb(n, r): if (r < 0 or r > n): return 0 r = min(r, n - r) return g1[n] * g2[r] * g2[n - r] % MOD g1 = [1, 1] # 元テーブル g2 = [1, 1] # 逆元テーブル inverse = [0, 1] # 逆元テーブル計算用テーブル for i in range(2, n + 1): g1.append((g1[-1] * i) % MOD) inverse.append((-inverse[MOD % i] * (MOD // i)) % MOD) g2.append((g2[-1] * inverse[-1]) % MOD) ma = 0 mi = 0 for i in range(n): ma += a[i] * cmb(i, k - 1) mi += a[i] * cmb(n - i - 1, k - 1) print(((ma - mi) % MOD))
p02804
from functools import lru_cache @lru_cache(None) def factrial(n): ans = 1 for i in range(1, n+1): ans *= i return ans @lru_cache(None) def combinations(n, r,mod): return (factrial(n) // (factrial(n - r) * factrial(r))) % mod def main(): n, k = list(map(int, input().split())) mod = 10 ** 9 + 7 A = tuple([x % mod for x in sorted(map(int, input().split()))]) ans = 0 for i, a in enumerate(A[k - 1:], k - 1): ans += (a * combinations(i, k - 1,mod)) % mod ans %= mod for i, a in enumerate(A[: n - k + 1], 1): ans -= (a * combinations(n - i, k - 1,mod)) % mod ans %= mod print(ans) if __name__ == "__main__": main()
from functools import lru_cache n, k = list(map(int, input().split())) A = sorted(map(int, input().split())) mod = 10 ** 9 + 7 # 階乗とその逆元の計算 factrial = [0 for _ in range(n + 1)] factrial[0] = 1 for i in range(1, n + 1): factrial[i] = (factrial[i - 1] * i) % mod inverse_factrial = list() for f in factrial: inverse_factrial.append(pow(f, -1, mod)) @lru_cache(maxsize=None) def nCr(n, r): return (factrial[n] * inverse_factrial[r] * inverse_factrial[n - r]) % mod ans = 0 # 最大値の和 for i, a in enumerate(A[k - 1:], k - 1): ans += ((a % mod) * nCr(i, k-1)) % mod ans %= mod # 最小値の和 A.reverse() for i, a in enumerate(A[k - 1:], k - 1): ans -= ((a % mod) * nCr(i, k-1)) % mod ans %= mod print(ans)
p02804
import math N, K = list(map(int, input().split())) A = sorted(list(map(int, input().split()))) Ar = A[::-1] Ai = [Ar[i] - A[i] for i in range(N)] ans = 0 if K > N//2: n, r = N-1, K-1 C = math.factorial(n) // (math.factorial(n - r) * math.factorial(r)) for i in range(N-K+1): ans += Ai[i] * C C *= N-i-K if N-i-1 != 0: C //= N-i-1 else: C = 1 for i in range(N-K, -1, -1): ans += Ai[i] * C C *= N - i if N-K+1 - i != 0: C //= N-K+1 - i print((ans % 1000000007))
N, K = list(map(int, input().split())) MOD = 10**9+7 A = [a % MOD for a in sorted(list(map(int, input().split())))] MIN, MAX = 0, 0 def div_MOD(a): # (a^{-1} mod MOD) をフェルマーの小定理より求める return pow(a, MOD - 2, MOD) # a^{-1} = a^{p-2} (mod p) C = [0]*(K-1) + [1] for n in range(K, N): C.append((C[n-1] * n * div_MOD(n-(K-1))) % MOD) for i in range(N-K+1): MIN = (MIN + (A[i] * C[N-i-1]) % MOD) %MOD for i in range(N-K+1): MAX = (MAX + (A[N-1-i] * C[N-i-1]) % MOD) %MOD print(((MAX - MIN) % MOD))
p02804
def prepare(N, MOD): fac = [None] * (N+2) finv = [None] * (N+2) inv = [None] * (N+2) fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 inv[1] = 1 for i in range(2, N+1): fac[i] = fac[i - 1] * i % MOD inv[i] = MOD - inv[MOD % i] * (MOD // i) % MOD finv[i] = finv[i - 1] * inv[i] % MOD return fac, finv def combination(N, K, fac, finv, MOD): if N < K: return 0 if N < 0 or K < 0: return 0 else: return fac[N] * (finv[K] * finv[N - K] % MOD) % MOD MOD = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() ans = 0 for i in range(N): fac, finv = prepare(i, MOD) comb = combination(i, K-1, fac, finv, MOD) ans += A[i] * comb A.sort(reverse=True) for i in range(N): fac, finv = prepare(i, MOD) comb = combination(i, K-1, fac, finv, MOD) ans -= A[i] * comb ans %= MOD print(ans)
def prepare(N, MOD): fac = [None] * (N+2) finv = [None] * (N+2) inv = [None] * (N+2) fac[0] = fac[1] = 1 finv[0] = finv[1] = 1 inv[1] = 1 for i in range(2, N+1): fac[i] = fac[i - 1] * i % MOD inv[i] = MOD - inv[MOD % i] * (MOD // i) % MOD finv[i] = finv[i - 1] * inv[i] % MOD return fac, finv def combination(N, K, fac, finv, MOD): if N < K: return 0 if N < 0 or K < 0: return 0 else: return fac[N] * (finv[K] * finv[N - K] % MOD) % MOD MOD = 10 ** 9 + 7 N, K = list(map(int, input().split())) A = list(map(int, input().split())) A.sort() fac, finv = prepare(N, MOD) ans = 0 for i in range(N): comb = combination(i, K-1, fac, finv, MOD) ans += A[i] * comb A.sort(reverse=True) for i in range(N): comb = combination(i, K-1, fac, finv, MOD) ans -= A[i] * comb ans %= MOD print(ans)
p02804
""" ジャガー「わからん」 先にmax,minそれぞれの和を求める """ import sys input = sys.stdin.readline mod = 10**9+7 def getComb(n, k, MOD): if n < k: return 0 if n-k < k: k = n-k # n!/(n-k)! comb = 1 for x in range(n-k+1, n+1): comb = (comb * x) % MOD # k! d = 1 for x in range(1, k+1): d = (d * x) % MOD # n!/((n-k)!*k!) comb *= pow(d, MOD-2, MOD) return comb % MOD def main(): N,K = list(map(int,input().split())) A = sorted([int(i) for i in input().split()]) cmb = [0] * (N-K+1) for i in range(N-K+1): cmb[i] = getComb(i+(K-1),K-1,mod) sum_min = 0 sum_max = 0 for i in range(N): if i >= K-1: sum_max = (sum_max + (cmb[i-(K-1)] * A[i]) % mod) % mod if i <= N-K: sum_min = (sum_min + (cmb[(N-K)-i] * A[i]) % mod) % mod answer = (sum_max - sum_min) % mod print(answer) if __name__ == "__main__": main()
import sys input = sys.stdin.readline sys.setrecursionlimit(10**6) def getComb(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % p N,K = list(map(int,input().split())) A = sorted([int(i) for i in input().split()]) # ref: https://www.planeta.tokyo/entry/5195/ mod = 10**9+7 fact = [1, 1] factinv = [1, 1] inv = [0, 1] for i in range(2,N+1): fact.append((fact[-1] * i) % mod) inv.append((-inv[mod % i] * (mod // i)) % mod) factinv.append((factinv[-1] * inv[-1]) % mod) cmb = [0] * (N-K+1) for i in range(N-K+1): cmb[i] = getComb(i+(K-1),K-1,mod) sum_max = 0 for i in range(K-1,N): sum_max = (sum_max + cmb[i-(K-1)] * A[i]) % mod sum_min = 0 for i in range(N-K,-1,-1): sum_min = (sum_min + cmb[(N-K)-i] * A[i]) % mod answer = sum_max - sum_min print((answer % mod))
p02804
import sys input = sys.stdin.readline sys.setrecursionlimit(10**6) def getComb(n, r, p): if (r < 0) or (n < r): return 0 r = min(r, n - r) return fact[n] * factinv[r] * factinv[n-r] % p N,K = list(map(int,input().split())) A = sorted([int(i) for i in input().split()]) # ref: https://www.planeta.tokyo/entry/5195/ mod = 10**9+7 fact = [1, 1] factinv = [1, 1] inv = [0, 1] for i in range(2,N+1): fact.append((fact[-1] * i) % mod) inv.append((-inv[mod % i] * (mod // i)) % mod) factinv.append((factinv[-1] * inv[-1]) % mod) cmb = [0] * (N-K+1) for i in range(N-K+1): cmb[i] = getComb(i+(K-1),K-1,mod) sum_max = 0 for i in range(K-1,N): sum_max = (sum_max + cmb[i-(K-1)] * A[i]) % mod sum_min = 0 for i in range(N-K,-1,-1): sum_min = (sum_min + cmb[(N-K)-i] * A[i]) % mod answer = sum_max - sum_min print((answer % mod))
import sys input = sys.stdin.readline sys.setrecursionlimit(10**6) class Combination(): # コンストラクタ def __init__(self, N:int, P:int): self.N = N self.P = P # fact[i] = (i! mod P) self.fact = [1, 1] # factinv[i] = ((i!)^(-1) mod P) self.factinv = [1, 1] # factinv 計算用 self.inv = [0, 1] for i in range(2, N+1): self.fact.append((self.fact[-1] * i) % P) self.inv.append((-self.inv[P % i] * (P // i)) % P) self.factinv.append((self.factinv[-1] * self.inv[-1]) % P) # nCk (mod P) (ただし、n<=N) def getComb(self, n:int, k:int): if (k < 0) or (n < k): return 0 k = min(k, n - k) return self.fact[n] * self.factinv[k] * self.factinv[n-k] % self.P def main(): N,K = list(map(int,input().split())) A = sorted([int(i) for i in input().split()]) mod = 10**9+7 COMB = Combination(N,mod) cmb = [0] * (N-K+1) for i in range(N-K+1): cmb[i] = COMB.getComb(i+(K-1),K-1) sum_max = 0 for i in range(K-1,N): sum_max = (sum_max + cmb[i-(K-1)] * A[i]) % mod sum_min = 0 for i in range(N-K,-1,-1): sum_min = (sum_min + cmb[(N-K)-i] * A[i]) % mod answer = sum_max - sum_min print((answer % mod)) if __name__ == "__main__": main()
p02804
from math import factorial p=10**9+7 n,k=list(map(int,input().split())) A=[int(i) for i in input().split()] A.sort() def nck(n,k): return factorial(n)//factorial(n-k)//factorial(k) ans=0 if k==1: ans=0 else: for i in range(n): for j in range(k-1,n-i): ans+=(A[i+j]-A[i])*nck(j-1,k-2) ans=ans%p print(ans)
n,k=list(map(int,input().split())) arr=[int(i) for i in input().split()] arr.sort() mod=10**9+7 #nCk factorial=[1] for i in range(1, n+1): factorial.append(factorial[-1] * i % mod) inv_factorial = [-1] * (n+1) inv_factorial[-1] = pow(factorial[-1], mod-2, mod) for i in reversed(list(range(n))): inv_factorial[i] = inv_factorial[i+1] * (i+1) % mod def fact(n): return factorial[n] def nck(n, k): if k>n or k<0: return 0 else: return factorial[n] * inv_factorial[n-k] * inv_factorial[k] %mod m=0 for i in range(n): m%=mod m+=arr[i]*nck(n-i-1, k-1) M=0 for i in range(n-1, -1, -1): M%=mod M+=arr[i]*nck(i, k-1) print(((M-m)%mod))
p02804