結果
問題 | No.1035 Color Box |
ユーザー |
![]() |
提出日時 | 2020-04-24 21:44:56 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 15 ms / 2,000 ms |
コード長 | 2,578 bytes |
コンパイル時間 | 1,561 ms |
コンパイル使用メモリ | 170,580 KB |
実行使用メモリ | 6,820 KB |
最終ジャッジ日時 | 2024-10-15 02:39:15 |
合計ジャッジ時間 | 2,597 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge3 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 36 |
ソースコード
#include <bits/stdc++.h>int ri() {int n;scanf("%d", &n);return n;}#define MOD 1000000007template<int mod>struct ModInt{int x;ModInt():x(0){}ModInt(long long y):x(y>=0?y%mod:(mod-(-y)%mod)%mod){}ModInt &operator+=(const ModInt &p){if((x+=p.x)>=mod)x-=mod;return *this;}ModInt &operator-=(const ModInt &p){if((x+=mod-p.x)>=mod)x-=mod;return *this;}ModInt &operator*=(const ModInt &p){x=(int)(1LL*x*p.x%mod);return *this;}ModInt &operator/=(const ModInt &p){*this*=p.inverse();return *this;}ModInt &operator^=(long long p){ModInt res = 1;for (; p; p >>= 1) {if (p & 1) res *= *this;*this *= *this;}return *this = res;}ModInt operator-()const{return ModInt(-x);}ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;}ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;}ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;}ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;}ModInt operator^(long long p)const{return ModInt(*this)^=p;}bool operator==(const ModInt &p)const{return x==p.x;}bool operator!=(const ModInt &p)const{return x!=p.x;}explicit operator int() const { return x; } // added by QCFiumModInt operator=(const int p) {x = p; return ModInt(*this);} // added by QCFiumModInt inverse()const{int a=x,b=mod,u=1,v=0,t;while(b>0){t=a/b;a-=t*b;std::swap(a,b);u-=t*v;std::swap(u,v);}return ModInt(u);}friend std::ostream &operator<<(std::ostream &os,const ModInt<mod> &p){return os<<p.x;}friend std::istream &operator>>(std::istream &is,ModInt<mod> &a){long long x;is>>x;a=ModInt<mod>(x);return (is);}};typedef ModInt<MOD> mint;struct MComb {std::vector<mint> fact;std::vector<mint> inversed;MComb(int n) { // O(n+log(mod))fact = std::vector<mint>(n+1,1);for (int i = 1; i <= n; i++) fact[i] = fact[i-1]*mint(i);inversed = std::vector<mint>(n+1);inversed[n] = fact[n] ^ (MOD-2);for (int i = n - 1; i >= 0; i--) inversed[i]=inversed[i+1]*mint(i+1);}mint ncr(int n, int r) {return (fact[n] * inversed[r] * inversed[n-r]);}mint npr(int n, int r) {return (fact[n] * inversed[n-r]);}mint nhr(int n, int r) {assert(n+r-1 < (int)fact.size());return ncr(n+r-1, r);}};int main() {int n = ri(), m = ri();MComb com(n + m + 1);mint res = 0;for (int i = 0; i < m; i++) {mint cur = (mint(m - i) ^ n) * com.ncr(m, i);if (i & 1) res -= cur;else res += cur;}std::cout << res << std::endl;return 0;}