結果

問題 No.2550 MORE! JUMP! MORE!
コンテスト
ユーザー dyktr_06
提出日時 2023-11-22 08:10:07
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 29 ms / 2,000 ms
コード長 3,284 bytes
コンパイル時間 1,995 ms
コンパイル使用メモリ 196,256 KB
最終ジャッジ日時 2025-02-17 22:51:42
ジャッジサーバーID
（参考情報） 		judge5 / judge5
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ファイルパターン 結果
other AC * 40
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;

template <long long Modulus>
struct ModInt{
    long long val;
    constexpr ModInt(const long long &_val = 0) noexcept : val(_val) {
        normalize();
    }
    void normalize(){
        val = (val % Modulus + Modulus) % Modulus;
    }
    inline ModInt& operator+=(const ModInt& rhs) noexcept {
        if(val += rhs.val, val >= Modulus) val -= Modulus;
        return *this;
    }
    inline ModInt& operator-=(const ModInt& rhs) noexcept {
        if(val -= rhs.val, val < 0) val += Modulus;
        return *this;
    }
    inline ModInt& operator*=(const ModInt& rhs) noexcept {
        val = val * rhs.val % Modulus;
        return *this;
    }
    inline ModInt& operator/=(const ModInt& rhs) noexcept {
        val = val * inv(rhs.val).val % Modulus;
        return *this;
    }
    inline ModInt& operator++() noexcept {
        if(++val >= Modulus) val -= Modulus;
        return *this;
    }
    inline ModInt operator++(int) noexcept {
        ModInt t = val;
        if(++val >= Modulus) val -= Modulus;
        return t;
    }
    inline ModInt& operator--() noexcept {
        if(--val < 0) val += Modulus;
        return *this;
    }
    inline ModInt operator--(int) noexcept {
        ModInt t = val;
        if(--val < 0) val += Modulus;
        return t;
    }
    inline ModInt operator-() const noexcept { return (Modulus - val) % Modulus; }
    inline ModInt inv(void) const { return inv(val); }
    ModInt inv(const long long& n) const {
        long long a = n, b = Modulus, u = 1, v = 0;
        while(b){
            long long t = a / b;
            a -= t * b; swap(a, b);
            u -= t * v; swap(u, v);
        }
        u %= Modulus;
        if(u < 0) u += Modulus;
        return u;
    }
    friend inline ModInt operator+(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) += rhs; }
    friend inline ModInt operator-(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) -= rhs; }
    friend inline ModInt operator*(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) *= rhs; }
    friend inline ModInt operator/(const ModInt& lhs, const ModInt& rhs) noexcept { return ModInt(lhs) /= rhs; }
    friend inline bool operator==(const ModInt& lhs, const ModInt& rhs) noexcept { return lhs.val == rhs.val; }
    friend inline bool operator!=(const ModInt& lhs, const ModInt& rhs) noexcept { return lhs.val != rhs.val; }
    friend inline istream& operator>>(istream& is, ModInt& x) noexcept {
        is >> x.val;
        x.normalize();
        return is;
    }
    friend inline ostream& operator<<(ostream& os, const ModInt& x) noexcept { return os << x.val; }
};

const long long MOD = 998244353;

using mint = ModInt<MOD>;

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

    int n; cin >> n;
    vector<mint> a(n);
    for(int i = 0; i < n; i++){
        cin >> a[i];
    }

    vector<mint> pow2(n + 1, 1);
    for(int i = 1; i <= n; i++){
        pow2[i] = pow2[i - 1] * 2;
    }

    mint ans = 0;
    for(long long i = 1; i <= n; i++){
        mint res = pow2[max(0LL, i - 2)] * (i - 1) + pow2[i - 1];
        res *= a[i - 1];
        res *= pow2[max(0LL, n - i - 1LL)];
        ans += res;
    }
    cout << ans << endl;
}
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