Submission #1084747

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084747		zxcigan	Trains (BOI24_trains)	C++17	21 / 100	1211 ms	1048576 KiB

Main

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define int long long
const int N = 2e5;
const int mod = 1e9 + 7;
int dp[N];
vector<int> g[N];
int32_t main() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif // LOCAL
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        int x, d;
        cin >> d >> x;
        if (x && d) {
            for (int j = 1; j <= x; ++j) {
                if (i + d * j > n) break;
//                if (i == 1) cout << i << ' ' << d << ' ' << j << ' ' << i + d * j << '\n';
                g[i + d * j].push_back(i);
            }
        }
    }
    dp[1] = 1;
    int s = 0;
    for (int i = 1; i <= n; ++i) {
        for (auto to : g[i]) {
            (dp[i] += dp[to]) %= mod;
        }
        (s += dp[i]) %= mod;
    }
//    cout << g[2].size() << '\n';
    cout << s << '\n';
}

• Subtask 1: 8 / 8
• Subtask 2: 13 / 13
• Subtask 3: 0 / 16
• Subtask 4: 0 / 34
• Subtask 5: 0 / 29