結果
問題 | No.1702 count good string |
ユーザー |
|
提出日時 | 2021-10-08 22:50:48 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 9 ms / 2,000 ms |
コード長 | 3,363 bytes |
コンパイル時間 | 2,423 ms |
コンパイル使用メモリ | 201,728 KB |
最終ジャッジ日時 | 2025-01-24 23:04:40 |
ジャッジサーバーID (参考情報) |
judge2 / judge1 |
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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 ll = long long;using std::cin;using std::cout;using std::endl;std::mt19937 rnd(std::chrono::steady_clock::now().time_since_epoch().count());template <class T>inline bool chmax(T &a, T b){if (a < b){a = b;return 1;}return 0;}template <class T>inline bool chmin(T &a, T b){if (a > b){a = b;return 1;}return 0;}const int inf = (int)1e9 + 7;const long long INF = 1LL << 60;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;std::swap(a -= t * b, b);std::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 std::ostream &operator<<(std::ostream &os, const ModInt &p){return os << p.x;}friend std::istream &operator>>(std::istream &is, ModInt &a){int64_t t;is >> t;a = ModInt<mod>(t);return (is);}static int get_mod() { return mod; }};constexpr int mod = (int)1e9 + 7;using mint = ModInt<mod>;void solve([[maybe_unused]] int CASE){int n;std::string s;cin >> n >> s;const std::string t = "yukicoder";std::vector dp(2, std::vector(2, std::vector<mint>(t.size() + 1)));int cur = 0, nxt = 1;dp[0][0][0] = 1;for (int i = 0; i < n; ++i){for (int j = 0; j < 2; ++j){for (int k = 0; k <= (int)t.size(); ++k){dp[nxt][j][k] = 0;}}for (int j = 0; j < 2; ++j){for (int k = 0; k <= (int)t.size(); ++k){dp[nxt][j][k] += dp[cur][j][k];if (k + 1 <= (int)t.size()){if (s[i] == '?' and j == 0){dp[nxt][1][k + 1] += dp[cur][j][k];}if (s[i] == t[k]){dp[nxt][j][k + 1] += dp[cur][j][k];}}}}std::swap(cur, nxt);}mint res = 0;for (int i = 0; i < 2; ++i){res += dp[cur][i][(int)t.size()];}cout << res << "\n";}int main(){std::cin.tie(nullptr);std::ios::sync_with_stdio(false);int kkt = 1;// cin >> kkt;for (int jupi = 1; jupi <= kkt; jupi++)solve(jupi);return 0;}