#1168402 (C++17) No.3566 Subsequence Sum

• 問題: No.3566 Subsequence Sum
• ユーザー: GOTKAKO
• 提出日時: 2026-06-06 00:02:21
• 言語: C++17 (gcc 15.2.0 + boost 1.89.0)
• 結果: AC
• 実行時間: 626 ms / 2,000 ms
• コード長: 5,154 bytes
• コンパイル時間: 2,353 ms
• コンパイル使用メモリ: 229,208 KB
• 実行使用メモリ: 98,172 KB
• 最終ジャッジ日時: 2026-06-06 00:02:35
• 合計ジャッジ時間: 5,834 ms
• ジャッジサーバーID （参考情報）: judge1_1 / judge2_0

ファイルパターン	結果
sample	AC * 3
other	AC * 15

ソースコード

#include <bits/stdc++.h>
using namespace std;

//入力が必ず-mod<=a<modの時.
template<const int mod> //mod<2^30.
struct modint{ //mod変更が不可能.
    public:
    long long v;
    static void setmod(int m){} //飾り.
    static constexpr long long getmod(){return mod;}
    modint():v(0){}
    template<typename T>
    modint(T a):v(a){if(v < 0) v += mod;}
    long long val()const{return v;}
 
    modint &operator=(const modint &b) = default;
    modint &operator+()const{return (*this);}
    modint operator-()const{return modint(0)-(*this);}
    modint operator+(const modint b)const{return modint(v)+=b;}
    modint operator-(const modint b)const{return modint(v)-=b;}
    modint operator*(const modint b)const{return modint(v)*=b;}
    modint operator/(const modint b)const{return modint(v)/=b;}
    modint &operator+=(const modint b){
        v += b.v; if(v >= mod) v -= mod;
        return *this;
    }
    modint &operator-=(const modint b){
        v -= b.v; if(v < 0) v += mod; 
        return *this;
    }   
    modint &operator*=(const modint b){v = v*b.v%mod; return *this;}
    modint &operator/=(modint b){ //b!=0 mod素数が必須.
        assert(b.v != 0);
        (*this) *= b.pow(mod-2);
        return *this;
    }
    modint pow(long long n)const{
        modint ret = 1,p = v;
        if(n < 0) p = p.inv(),n = -n;
        while(n){
            if(n&1) ret *= p;
            p *= p; n >>= 1;
        }
        return ret;
    }
    modint inv()const{return pow(mod-2);} //素数mod必須.
 
    modint &operator++(){*this += 1; return *this;}
    modint &operator--(){*this -= 1; return *this;}
    modint operator++(int){modint ret = *this; *this += 1; return ret;}
    modint operator--(int){modint ret = *this; *this -= 1; return ret;}
    friend bool operator==(const modint a,const modint b){return a.v==b.v;}
    friend bool operator!=(const modint a,const modint b){return a.v!=b.v;}
    friend bool operator<(const modint a,const modint b){return a.v<b.v;}
    friend bool operator<=(const modint a,const modint b){return a.v<=b.v;}
    friend bool operator>=(const modint a,const modint b){return a.v>=b.v;}
    friend bool operator>(const modint a,const modint b){return a.v>b.v;}
    friend ostream &operator<<(ostream &os,const modint a){return os<<a.v;}
    friend istream &operator>>(istream &is,modint &a){ //入力はmodをとってくれる.
        long long x; is >> x; x %= mod;
        a = modint(x); return is;
    }
};
using mint = modint<998244353>; const long long mod = 998244353;

struct SS{
    mint v,mul,add;
    SS operator*(SS b){
        return {v*b.v,mul*b.mul,add*b.mul+v*b.add};
    }
    SS operator+(SS b){
        return {v+b.v,mul+b.mul,add+b.add};
    }
    SS operator+=(SS b){
        return *this = *this+b;
    }
    SS operator*=(SS b){
        return *this = *this*b;
    }
};

template<typename T>
vector<vector<T>> multima(vector<vector<T>> &A,vector<vector<T>> &B){
    assert(A.at(0).size() == B.size() && B.size());
    int H = A.size(),W = B.at(0).size();
    vector<vector<T>> ret(H,vector<T>(W));
    for(int i=0; i<H; i++) for(int k=0; k<W; k++){
        for(int l=0; l<A.at(i).size(); l++){
            ret.at(i).at(k) += B.at(l).at(k)*A.at(i).at(l);
        }
    }
    return ret; //計算できる行列のみ.
}
template<typename T>
vector<vector<T>> Powmat(vector<vector<T>> A,vector<vector<T>> B,long long N){ //return A^N*B ABは行列;
    //n*n行列A n*1行列Bと想定 O(n^3*logN).
    assert(A.size() && A.size() == A.at(0).size() && N >= 0);
    while(N){
        if(N&1) B = multima(A,B);
        A = multima(A,A); N >>= 1;
    }
    return B;
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    string s; cin >> s;
    int N = s.size(),K; cin >> K;
    vector<vector<int>> next(N,vector<int>(10,N));
    for(int i=N-2; i>=0; i--){
        next.at(i) = next.at(i+1);
        next.at(i).at(s.at(i+1)-'0') = i+1;
    }
    vector<int> C(10,-1);
    for(int i=0; i<N; i++){
        int c = s.at(i)-'0';
        if(C.at(c) != -1) continue;
        C.at(c) = i;
    }
    vector<int> look;
    for(int i=0; i<10; i++) if(C.at(i) != -1) look.push_back(i);
 
    int n = look.size();
    vector<vector<SS>> A(n+1,vector<SS>(n+1)),B(n+1,vector<SS>(1));
    for(int p=0; p<n; p++){
        int c = look.at(p);
        if(c) B.at(p).at(0) = {1,1,c};
        vector<SS> dp(N);
        dp.at(C.at(c)) = {1,1,0};
        vector<SS> V(n+1);
        for(int i=C.at(c); i<N; i++){
            SS v = dp.at(i);
            V.at(n) += v;
            v = {v.v,v.mul*10,v.add*10};
            for(int k=0; k<n; k++){
                int c2 = look.at(k);
                int to = next.at(i).at(c2);
                SS now = {v.v,v.mul,v.add+v.v*c2};
                if(to == N){
                    V.at(k) += now;
                }    
                else dp.at(to) += now;
            }
        }
        for(int i=0; i<=n; i++) A.at(i).at(p) = V.at(i);
    }
    A.at(n).at(n) = {1,1,0};
    B = Powmat(A,B,K);
    auto [v1,v2,v3] = B.at(n).at(0);
    cout << v3 << endl; return 0;
    cout << v1 << " " << v2 << " " << v3 << endl;
}