結果
問題 | No.2747 Permutation Adjacent Sum |
ユーザー |
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提出日時 | 2024-04-21 04:28:59 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 2,627 ms / 3,000 ms |
コード長 | 2,822 bytes |
コンパイル時間 | 4,322 ms |
コンパイル使用メモリ | 262,948 KB |
最終ジャッジ日時 | 2025-02-21 07:48:48 |
ジャッジサーバーID (参考情報) |
judge1 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 40 |
ソースコード
#include<bits/stdc++.h>using namespace std;//* ATCODER#include<atcoder/all>using namespace atcoder;typedef modint998244353 mint;//*//* BOOST MULTIPRECISION#include<boost/multiprecision/cpp_int.hpp>using namespace boost::multiprecision;//*/typedef long long ll;#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)template <typename T> bool chmin(T &a, const T &b) {if (a <= b) return false;a = b;return true;}template <typename T> bool chmax(T &a, const T &b) {if (a >= b) return false;a = b;return true;}template <typename T> T max(vector<T> &a){assert(!a.empty());T ret = a[0];for (int i=0; i<(int)a.size(); i++) chmax(ret, a[i]);return ret;}template <typename T> T min(vector<T> &a){assert(!a.empty());T ret = a[0];for (int i=0; i<(int)a.size(); i++) chmin(ret, a[i]);return ret;}template <typename T> T sum(vector<T> &a){T ret = 0;for (int i=0; i<(int)a.size(); i++) ret += a[i];return ret;}//defmodfactconst int COMinitMAX = 2222222;mint fact[COMinitMAX+1], factinv[COMinitMAX+1];void modfact(){fact[0] = 1;for (int i=1; i<=COMinitMAX; i++){fact[i] = fact[i-1] * i;}factinv[COMinitMAX] = fact[COMinitMAX].inv();for (int i=COMinitMAX-1; i>=0; i--){factinv[i] = factinv[i+1] * (i+1);}}mint cmb(int a, int b){if (a<b || b<0) return mint(0);return fact[a]*factinv[b]*factinv[a-b];}//--------vector<mint> poly_inv(vector<mint> &a, int M = -314159265){if (M == -314159265) M = (int)a.size();else if (M <= 0) return {};int n = a.size();mint r = a[0].pow((ll)(mint::mod())-2);int m = 1;vector<mint> res = {r};while (m < M){vector<mint> f = a;f.resize(2 * m);vector<mint> g = res;g.resize(2 * m);internal::butterfly(f);internal::butterfly(g);for (int i=0; i<2*m; i++){f[i] = f[i] * g[i];}internal::butterfly_inv(f);for (int i=0; i<m; i++){f[i] = f[i + m];}for (int i=0; i<m; i++){f[i + m] = 0;}internal::butterfly(f);for (int i=0; i<2*m; i++){f[i] = f[i] * g[i];}internal::butterfly_inv(f);mint iz = mint(2*m).inv();iz = -iz * iz;for (int i=0; i<m; i++){f[i] = f[i] * iz;}res.insert(res.end(), f.begin(), f.begin()+m);m <<= 1;}res.resize(M);return res;}int main(){modfact();ll n, k; cin >> n >> k;vector<mint> f(k+2);vector<mint> g(k+2);mint val = 1;rep(i,0,k+2){val *= n + 1;f[i] = factinv[i + 1] * val;g[i] = factinv[i + 1];}vector<mint> h = convolution(f, poly_inv(g));h.resize(k+2);mint ans = n * h[k] * fact[k] - h[k+1] * fact[k+1];ans *= 2;if (n >= 500'000'000){ans *= 15814281;rep(i,500'000'000,n){ans *= i;}}else{rep(i,2,n){ans *= i;}}cout << ans.val() << '\n';}