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Submission #455294

# Submission time Handle Problem Language Result Execution time Memory
455294 2021-08-05T18:49:36 Z _Avocado_ Fountain (eJOI20_fountain) C++14
100 / 100
 627 ms 71860 KB 
#include <bits/stdc++.h>
#define int int64_t
using namespace std;

vector<vector<int>>graph, up, cap;
vector<int>c, d;
int timer = 0;
int l = 31;

void lift(int v, int par){
	up[v][0] = par;
	cap[v][0] = c[v];
	
	for(int i = 1; i<=l; ++i){
		up[v][i] = up[up[v][i-1]][i-1];
		cap[v][i] = cap[v][i-1] + cap[up[v][i-1]][i-1];
	}
	
	for(auto u: graph[v]){
		if(u != par) lift(u, v);
	}
	
}

int query(int u, int x){
	
	int cur = 0;
	
	for(int i = l; i>=0; --i){
		if(cap[u][i] + cur < x){
			cur += cap[u][i];
			u = up[u][i];
		}
		
	}
	
	return u;
}

signed main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	int n, q; cin>>n>>q;
	
	up.assign(n+1, vector<int>(l+1));
	cap.assign(n+1, vector<int>(l+1));
	
	c.assign(n+1, 0);
	d.assign(n+1, 0);
	
	for(int i = 1; i<=n; ++i){
		int a, b; cin>>a>>b;
		c[i] = b;
		d[i] = a;
	}
	
	
	stack<pair<int, int>>s;
	graph.assign(n+1, vector<int>());
	vector<int>p(n+1);
	
	for(int i = 1; i<=n; ++i){
		while(!s.empty() && s.top().first < d[i]){
			p[s.top().second] = i;
			s.pop();
		}
		s.push({d[i], i});
	}
	
	while(!s.empty()){
		p[s.top().second] = 0;
		s.pop();
	}
	
	
	for(int i = 1; i<=n; ++i){
		graph[p[i]].push_back(i);
	}
	
	lift(0, 0);
	
	
	
	for(int i = 0; i<q; ++i){
		int a, b; cin>>a>>b;
		cout<<query(a, b)<<'\n';
	}
		

}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 640 KB Output is correct
3 Correct 2 ms 716 KB Output is correct
4 Correct 2 ms 844 KB Output is correct
5 Correct 2 ms 972 KB Output is correct
6 Correct 2 ms 972 KB Output is correct
7 Correct 2 ms 844 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 436 ms 68020 KB Output is correct
2 Correct 480 ms 62676 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 1 ms 640 KB Output is correct
3 Correct 2 ms 716 KB Output is correct
4 Correct 2 ms 844 KB Output is correct
5 Correct 2 ms 972 KB Output is correct
6 Correct 2 ms 972 KB Output is correct
7 Correct 2 ms 844 KB Output is correct
8 Correct 436 ms 68020 KB Output is correct
9 Correct 480 ms 62676 KB Output is correct
10 Correct 2 ms 972 KB Output is correct
11 Correct 206 ms 37304 KB Output is correct
12 Correct 627 ms 71860 KB Output is correct
13 Correct 459 ms 67100 KB Output is correct
14 Correct 302 ms 66160 KB Output is correct
15 Correct 249 ms 65716 KB Output is correct