結果

問題 No.2613 Sum of Combination
ユーザー karinohitokarinohito
提出日時 2024-01-19 22:44:46
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 717 ms / 4,500 ms
コード長 3,606 bytes
コンパイル時間 4,617 ms
コンパイル使用メモリ 268,548 KB
最終ジャッジ日時 2025-02-18 21:26:02
ジャッジサーバーID
(参考情報)
judge1 / judge4
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 * 49
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 #

#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
#include <time.h> 
using namespace atcoder;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vvvb = vector<vvb>;
#define all(A) A.begin(),A.end()
#define rep(i, n) for (ll i = 0; i < (ll) (n); i++)
template<class T>
bool chmax(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p < q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}
template<class T>
bool chmin(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p > q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}
ll modPow(long long a, long long n, long long p) {
    if (n == 0) return 1; // 0乗にも対応する場合
    if (n == 1) return a % p;
    if (n % 2 == 1) return (a * modPow(a, n - 1, p)) % p;
    long long t = modPow(a, n / 2, p);
    return (t * t) % p;
}
ll cnt = 0;
ll gcd(ll(a), ll(b)) {
    cnt++;
    if (a == 0)return b;
    if (b == 0)return a;
    ll c = a;
    while (a % b != 0) {
        c = a % b;
        a = b;
        b = c;
    }
    return b;
}
ll sqrtz(ll N) {
    ll L = 0;
    ll R = sqrt(N) + 10000;
    while (abs(R - L) > 1) {
        ll mid = (R + L) / 2;
        if (mid * mid <= N)L = mid;
        else R = mid;
    }
    return L;
}


ll nzkon(ll N, ll K) {//
    return 0;
}


using mint = modint998244353;
using vm = vector<mint>;
using vvm = vector<vm>;
using vvvm = vector<vvm>;


vector<ll> fact, factinv, inv;
ll mod;
void prenCkModp(ll n) {
    fact.resize(n + 5);
    factinv.resize(n + 5);
    inv.resize(n + 5);
    fact[0] = fact[1] = 1;
    factinv[0] = factinv[1] = 1;
    inv[1] = 1;
    for (ll i = 2; i < n + 5; i++) {
        fact[i] = (fact[i - 1] * i) % mod;
        inv[i] = (mod - ((inv[mod % i] * (mod / i)) % mod) % mod) % mod;
        factinv[i] = (factinv[i - 1] * inv[i]) % mod;
    }
}
ll nCk(ll n, ll k) {
    if (n < k || k < 0) return 0;
    return (fact[n] * ((factinv[k] * factinv[n - k]) % mod) % mod);
}

bool DEB = 0;

vvm mul(vvm A, vvm B) {
    ll n = A.size();
    vvm res(n, vm(n, 0));
    rep(i, n)rep(j, n)rep(k, n)res[i][j] += A[i][k] * B[k][j];
    return res;
}


ll proot(ll P) {
    while (1) {
        ll N = rand() % P, x = 1;
        if (N == 0)continue;
        set<ll> S;
        rep(i, P) {
            S.insert(x);
            x *= N;
            x %= P;
        }
        if (S.size() == P - 1) return N;
    }
}


int main() {

    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    ll N, P;
    cin >> N >> P;
    mod = P;
    prenCkModp(P + 1);

    vll M;
    while (N > 0) {
        M.push_back(N % P);
        N /= P;
    }

    reverse(all(M));
    ll MN = M.size();

    ll r = proot(P);
    //cout<<r<<endl;
    vll rs(P);
    ll x = 1;
    vll rsinv(P);
    rep(i, P - 1) {
        rsinv[i] = x;
        rs[x] = i;
        x *= r;
        x %= P;
    }
    mint J = 1;
    vm U(P, 0);
    U[0]=0;
    for (auto m : M) {
        //cout<<m<<endl;
        vm NU(P, 0);
        for (ll r = 0; r <= m; r++) {
            NU[rs[nCk(m, r)]]++;
        }
        NU = convolution(U, NU);
        U.assign(P, 0);
        for (ll i = 0; i < NU.size(); i++) {
            U[i % (P-1)] += NU[i];
        }
        for (ll pr = 0; pr < m; pr++) {
            ll rr = nCk(m, pr);
            if (rr == 0)continue;
            U[rs[rr]]++;
        }
    }
    mint an = 1;
    rep(i, P)an += U[i] * rsinv[i];
    cout << an.val() << endl;

    


}
0