結果

問題 No.2058 Binary String
ユーザー square1001
提出日時 2022-08-26 23:43:26
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 8 ms / 2,000 ms
コード長 1,359 bytes
コンパイル時間 4,232 ms
コンパイル使用メモリ 155,304 KB
最終ジャッジ日時 2025-01-31 05:51:29
ジャッジサーバーID
（参考情報） 		judge5 / judge5
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 3
other AC * 23
権限があれば一括ダウンロードができます

ソースコード

diff #
プレゼンテーションモードにする

/*
    The technique on "constexpr" is derived from:
    https://atcoder.jp/contests/agc023/submissions/2435844
*/
#include <iostream>
constexpr int MOD = 998244353;
template<int N> class precalculation {
public:
    int inv[N];
    int d[N];
    constexpr precalculation() : inv(), d() {
        inv[1] = 1;
        for (int i = 2; i < N; i++) {
            inv[i] = (long long)(inv[MOD % i]) * (MOD - MOD / i) % MOD;
        }
        for (int i = 1; i < N; i++) {
            d[i] = 1;
        }
        for (int i = 2; i < N; i++) {
            if (d[i] == 1) {
                for (int j = i * 2; j < N; j += i) {
                    if (d[j] == 1) {
                        d[j] = i;
                    }
                }
            }
        }
    }
};
constexpr precalculation precalc = precalculation<200001>();
int modpow(int a, int b) {
    int answer = 1;
    while (b != 0) {
        if ((b & 1) == 1) {
            answer = (long long)(answer) * a % MOD;
        }
        a = (long long)(a) * a % MOD;
        b >>= 1;
    }
    return answer;
}
int p[200009];
int main() {
    int N, K;
    std::cin >> N >> K;
    N -= 1;
    for (int i = 1; i <= N; i++) {
        if (precalc.d[i] == 1) {
            p[i] = modpow(i, K);
        }
        else {
            p[i] = (long long)(p[precalc.d[i]]) * p[i / precalc.d[i]] % MOD;
        }
    }
    int mult = 1;
    int answer = 0;
    for (int i = 0; i <= N; i++) {
        answer = (answer + (long long)(p[i]) * mult) % MOD;
        mult = (long long)(mult) * (N - i) % MOD;
        mult = (long long)(mult) * precalc.inv[i + 1] % MOD;
    }
    std::cout << answer << '\n';
    return 0;
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0