Submission #690851

#	Time	Username	Problem	Language	Result	Execution time	Memory
690851		ismayil	Fountain (eJOI20_fountain)	C++17	100 / 100	281 ms	22104 KiB

fountain

#include <bits/stdc++.h>
#define ll long long
using namespace std;
const int MAX = 1e5 + 5, LOG = 20, INF = 2e9;
int up[MAX][LOG], sum[MAX][LOG], D[MAX];
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int n, q;
    cin>>n>>q;
    for (int i = 1; i <= n; i++) cin>>D[i]>>sum[i][0];
    
    D[n + 1] = INF;
    sum[n + 1][0] = INF;
    up[n + 1][0] = n + 1;

    stack<int> s;
    s.push(n + 1);
    for (int i = n; i >= 1; i--)
    {
        while(D[s.top()] <= D[i]) s.pop();
        up[i][0] = s.top();
        s.push(i);
    }
    for (int i = 1; i < LOG; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            up[j][i] = up[up[j][i - 1]][i - 1];
            sum[j][i] = sum[up[j][i - 1]][i - 1] + sum[j][i - 1];
        }
    }
    
    for (int i = 0; i < q; i++)
    {
        int r, v;
        cin>>r>>v;
        for (int j = LOG - 1; j >= 0; j--)
        {
            if(v > sum[r][j]){
                v -= sum[r][j];
                r = up[r][j];
            }
        }
        if(r == n + 1) cout<<0<<'\n';
        else cout<<r<<'\n';
    }
    
}

• Subtask 1: 30 / 30
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40