제출 #1217821

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1217821		asdfghqwert	Trains (BOI24_trains)	C++20	100 / 100	228 ms	282632 KiB

Main

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#define int     long long int
using namespace std;
typedef long long ll;

const int T = 350;
const int MOD = 1e9 + 7;

int32_t main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n; cin >> n;
    vector<pair<int , int >> se(n + 1);
    for(int i = 1 ; i <= n ; i++){
        cin >> se[i].first >> se[i].second;
    }

    vector<vector<ll>> a(n + 2*T + 1, vector<ll>(T + 1, 0));
    vector<ll>         dp(n + 2*T + 1, 0);

    for(int i = n; i >= 1; i--){
        ll f = se[i].first;
        ll s = se[i].second;

        if(f == 0){
            dp[i] = 1;
        }
        else if(f <= T){
            dp[i] = 1 + a[i + f][f];
            if(i + se[i].first * (se[i].second + 1) <= n) dp[i] -=a[i + f*(s+1)][f];
            dp[i] = (dp[i] % MOD + MOD) % MOD;
        }
        else {
            dp[i] = 1;
            for(int j = i + f; j <= min(n, i + f*s); j += f){
                dp[i] = (dp[i] + dp[j]) % MOD;
            }
        }
        for(int j = 1; j <= T; j++){
            a[i][j] = (a[i + j][j] + dp[i]) % MOD;
        }
    }

    cout << dp[1] << "\n";
}

• Subtask 1: 8 / 8
• Subtask 2: 13 / 13
• Subtask 3: 16 / 16
• Subtask 4: 34 / 34
• Subtask 5: 29 / 29