結果
問題 | No.1702 count good string |
ユーザー |
|
提出日時 | 2022-12-30 12:43:17 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 118 ms / 2,000 ms |
コード長 | 2,635 bytes |
コンパイル時間 | 2,000 ms |
コンパイル使用メモリ | 200,748 KB |
最終ジャッジ日時 | 2025-02-09 22:04:53 |
ジャッジサーバーID (参考情報) |
judge1 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 47 |
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 >;string yuki = "yukicoder";int main() {int N;string S;cin >> N >> S;int M = yuki.size();vector<vector<vector<mint>>> dp(N+1, vector<vector<mint>>(M+1, vector<mint>(2, 0)));dp[0][0][0] = 1;for (int i = 0; i < N; i++) {for (int j = 0; j <= M; j++) for (int k = 0; k < 2; k++) dp[i+1][j][k] += dp[i][j][k];for (int j = 0; j < M; j++) {for (int k = 0; k < 2; k++) {if (S[i] == yuki[j]) {dp[i+1][j+1][k] += dp[i][j][k];}if (k == 0 && S[i] == '?') {dp[i+1][j+1][k+1] += dp[i][j][k];}}}}cout << dp[N][M][0] + dp[N][M][1] << endl;}