結果
問題 | No.573 a^2[i] = a[i] |
ユーザー |
![]() |
提出日時 | 2019-04-03 20:43:54 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 14 ms / 2,000 ms |
コード長 | 3,454 bytes |
コンパイル時間 | 2,236 ms |
コンパイル使用メモリ | 171,168 KB |
実行使用メモリ | 5,248 KB |
最終ジャッジ日時 | 2024-12-23 06:33:39 |
合計ジャッジ時間 | 3,672 ms |
ジャッジサーバーID (参考情報) |
judge2 / judge5 |
(要ログイン)
ファイルパターン | 結果 |
---|---|
other | AC * 47 |
ソースコード
#include "bits/stdc++.h"using namespace std;#ifdef _DEBUG#include "dump.hpp"#else#define dump(...)#endif//#define int long long#define rep(i,a,b) for(int i=(a);i<(b);i++)#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)#define all(c) begin(c),end(c)const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;const int MOD = 1'000'000'007;template<class T> bool chmax(T &a, const T &b) { if (a < b) { a = b; return true; } return false; }template<class T> bool chmin(T &a, const T &b) { if (b < a) { a = b; return true; } return false; }template<int MOD>struct ModInt {static const int kMod = MOD;unsigned x;ModInt() :x(0) {}ModInt(signed x_) { x_ %= MOD; if (x_ < 0)x_ += MOD; x = x_; }ModInt(signed long long x_) { x_ %= MOD; if (x_ < 0)x_ += MOD; x = x_; }int get()const { return (int)x; }ModInt &operator+=(ModInt m) { if ((x += m.x) >= MOD)x -= MOD; return *this; }ModInt &operator-=(ModInt m) { if ((x += MOD - m.x) >= MOD)x -= MOD; return *this; }ModInt &operator*=(ModInt m) { x = (unsigned long long)x*m.x%MOD; return *this; }ModInt &operator/=(ModInt m) { return *this *= m.inverse(); }ModInt operator+(ModInt m)const { return ModInt(*this) += m; }ModInt operator-(ModInt m)const { return ModInt(*this) -= m; }ModInt operator*(ModInt m)const { return ModInt(*this) *= m; }ModInt operator/(ModInt m)const { return ModInt(*this) /= m; }ModInt operator-()const { return ModInt(MOD - x); }bool operator==(ModInt m)const { return x == m.x; }bool operator!=(ModInt m)const { return x != m.x; }ModInt inverse()const {signed a = x, b = MOD, u = 1, v = 0;while (b) {signed t = a / b;a -= t * b; swap(a, b);u -= t * v; swap(u, v);}if (u < 0)u += MOD;return ModInt(u);}};template<int MOD>ostream &operator<<(ostream &os, const ModInt<MOD> &m) { return os << m.x; }template<int MOD>istream &operator>>(istream &is, ModInt<MOD> &m) { signed long long s; is >> s; m = ModInt<MOD>(s); return is; };template<int MOD>ModInt<MOD> pow(ModInt<MOD> a, unsigned long long k) {ModInt<MOD> r = 1;while (k) {if (k & 1)r *= a;a *= a;k >>= 1;}return r;}using mint = ModInt<MOD>;// n < 10^7// 前計算 O(n)// 計算 O(1)// Verified: https://yukicoder.me/submissions/330366vector<mint> fact, factinv, inv;void precompute(int n) {int m = fact.size();if (n < m)return;n = min(n, mint::kMod - 1); // N >= kMod => N! = 0 (mod kMod)fact.resize(n + 1);factinv.resize(n + 1);inv.resize(n + 1);if (m == 0) {fact[0] = 1;m = 1;}for (int i = m; i <= n; i++)fact[i] = fact[i - 1] * i;factinv[n] = fact[n].inverse();for (int i = n; i >= m; i--)factinv[i - 1] = factinv[i] * i; // ((i-1)!)^(-1) = (i!)^(-1) * ifor (int i = m; i <= n; i++)inv[i] = factinv[i] * fact[i - 1];}mint C(int n, int k) {// Lucas's theoremif (n >= mint::kMod)return C(n % mint::kMod, k % mint::kMod) * C(n / mint::kMod, k / mint::kMod);precompute(n);return k > n ? 0 : fact[n] * factinv[n - k] * factinv[k];}mint P(int n, int k) {precompute(n);return k > n ? 0 : fact[n] * factinv[n - k];}mint H(int n, int k) {if (n == 0 && k == 0)return 1; // H(0,0) = C(-1,0) = 1return C(n + k - 1, k);}signed main() {cin.tie(0);ios::sync_with_stdio(false);int N; cin >> N;mint ans = 0;rep(i, 1, N + 1) {mint x = pow(mint(i), N - i);x *= C(N, i);ans += x;}cout << ans << endl;return 0;}