Submission #1033259

#	Time	Username	Problem	Language	Result	Execution time	Memory
1033259		borisAngelov	Trains (BOI24_trains)	C++17	21 / 100	2041 ms	1512 KiB

Main

#include <bits/stdc++.h>

using namespace std;

const int maxn = 100005;
const int mod = 1e9 + 7;

int n;
int d[maxn], x[maxn];
int dp[maxn];

void fastIO()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
}

int main()
{
    fastIO();

    cin >> n;

    for (int i = 1; i <= n; ++i)
    {
        cin >> d[i] >> x[i];
    }

    dp[1] = 1;
    int ans = 1;

    for (int i = 2; i <= n; ++i)
    {
        for (int j = i - 1; j >= 1; --j)
        {
            if (d[j] != 0 && (i - j) % d[j] == 0 && (i - j) / d[j] <= x[j])
            {
                dp[i] += dp[j];
                if (dp[i] >= mod) dp[i] -= mod;
            }
        }

        ans += dp[i];
        if (ans >= mod) ans -= mod;
    }

    cout << ans << endl;

    return 0;
}

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