Submission #995465

#	Time	Username	Problem	Language	Result	Execution time	Memory
995465		12345678	Trains (BOI24_trains)	C++17	16 / 100	13 ms	2584 KiB

Main

#include <bits/stdc++.h>

using namespace std;

const int nx=1e5+5, mod=1e9+7;

int n, d[nx], x[nx], dp[nx], res, sm=1;
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n;
    for (int i=1; i<=n; i++) cin>>d[i]>>x[i];
    dp[1]=1;
    pq.push({1+x[1]+1, dp[1]});
    for (int i=2; i<=n; i++)
    {
        while (!pq.empty()&&pq.top().first<=i) sm=((sm-pq.top().second)%mod+mod)%mod, pq.pop();
        dp[i]=sm;
        //cout<<"dp "<<i<<' '<<dp[i]<<'\n';
        sm=(sm+dp[i])%mod;
        pq.push({i+x[i]+1, dp[i]});
    }    
    for (int i=1; i<=n; i++) res=(res+dp[i])%mod;
    cout<<res;
}

/*
5
1 3
1 2
1 1
1 4
1 5
*/

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