제출 #964688

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
964688		pcc	Fountain (eJOI20_fountain)	C++17	100 / 100	248 ms	40788 KiB

fountain

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>

const int mxn = 1e5+10;
int N,Q;
vector<int> tree[mxn];
ll cap[mxn],dia[mxn];
vector<int> st;
int par[mxn][20];
ll sum[mxn][20];

void dfs(int now){
	sum[now][0] = cap[now];
	for(int i = 1;i<20;i++){
		par[now][i] = par[par[now][i-1]][i-1];
		sum[now][i] = sum[now][i-1]+sum[par[now][i-1]][i-1];
	}
	for(auto nxt:tree[now]){
		par[nxt][0] = now;
		dfs(nxt);
	}
	return;
}

ll calc(int now,int cnt){
	for(int i = 19;i>=0;i--){
		if(sum[now][i]<cnt){
			cnt -= sum[now][i];
			now = par[now][i];
		}
	}
	if(now == N+1)return 0;
	else return now;
}

int main(){
	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>N>>Q;
	cap[N+1] = dia[N+1] = 1e9+10;
	for(int i = 1;i<=N;i++)cin>>dia[i]>>cap[i];
	for(int i = 1;i<=N+1;i++){
		while(!st.empty()&&dia[st.back()]<dia[i]){
			tree[i].push_back(st.back());
			st.pop_back();
		}
		st.push_back(i);
	}
	par[N+1][0] = N+1;
	dfs(N+1);
	while(Q--){
		int a,b;
		cin>>a>>b;
		cout<<calc(a,b)<<'\n';
	}
	return 0;
}

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