結果
問題 | No.1035 Color Box |
ユーザー |
|
提出日時 | 2022-12-24 13:29:06 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 19 ms / 2,000 ms |
コード長 | 3,108 bytes |
コンパイル時間 | 2,067 ms |
コンパイル使用メモリ | 196,496 KB |
最終ジャッジ日時 | 2025-02-09 19:57:42 |
ジャッジサーバーID (参考情報) |
judge4 / judge2 |
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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>using namespace std;const int mod = 1000000007;template< int mod >struct ModInt {int x;ModInt() : x(0) {}ModInt(int64_t 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-() 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; }bool operator==(const ModInt &p) const { return x == p.x; }bool operator!=(const ModInt &p) const { return x != p.x; }ModInt inverse() const {int a = x, b = mod, u = 1, v = 0, t;while (b > 0) {t = a / b;swap(a -= t * b, b);swap(u -= t * v, v);}return ModInt(u);}ModInt pow(int64_t n) const {ModInt ret(1), mul(x);while (n > 0) {if (n & 1) ret *= mul;mul *= mul;n >>= 1;}return ret;}friend ostream &operator<<(ostream &os, const ModInt &p) {return os << p.x;}friend istream &operator>>(istream &is, ModInt &a) {int64_t t;is >> t;a = ModInt< mod >(t);return (is);}static int get_mod() { return mod; }};using mint = ModInt< mod >;template< typename T >struct Combination {vector< T > _fact, _rfact, _inv;Combination(int sz) : _fact(sz + 1), _rfact(sz + 1), _inv(sz + 1) {_fact[0] = _rfact[sz] = _inv[0] = 1;for (int i = 1; i <= sz; i++) _fact[i] = _fact[i - 1] * i;_rfact[sz] /= _fact[sz];for (int i = sz - 1; i >= 0; i--) _rfact[i] = _rfact[i + 1] * (i + 1);for (int i = 1; i <= sz; i++) _inv[i] = _rfact[i] * _fact[i - 1];}inline T fact(int k) const { return _fact[k]; }inline T rfact(int k) const { return _rfact[k]; }inline T inv(int k) const { return _inv[k]; }T P(int n, int r) const {if (r < 0 || n < r) return 0;return fact(n) * rfact(n - r);}T C(int p, int q) const {if (q < 0 || p < q) return 0;return fact(p) * rfact(q) * rfact(p - q);}T H(int n, int r) const {if (n < 0 || r < 0) return (0);return r == 0 ? 1 : C(n + r - 1, r);}};int main() {Combination<mint> com(300000);int N, M;cin >> N >> M;mint ans = mint(0);for (int i = 0; i <= M; i++) ans += mint((M-i)%2 ? -1 : 1) * com.C(M, i) * mint(i).pow(N);cout << ans << endl;}