Submission #592118

#	Time	Username	Problem	Language	Result	Execution time	Memory
592118		Iwanttobreakfree	Fountain (eJOI20_fountain)	C++98	100 / 100	717 ms	49528 KiB

fountain

#include <iostream>
#include <vector>
#include <stack>
using namespace std;
int bin_lift(int a,vector<vector<pair<int,long long>>>& p,int w){
    for(int i=17;i>=0;i--){
        if(p[a][i].second<w){
            w-=p[a][i].second;
            a=p[a][i].first;
        }
    }
    //cout<<w<<' ';
    return a;
}
void dfs(int a,int par,int w,vector<vector<pair<int,int>>>& g,vector<vector<pair<int,long long>>>& p){
    //cout<<a<<' '<<par<<'\n';
    p[a][0]={par,w};
    for(int i=1;i<18;i++)p[a][i]={p[p[a][i-1].first][i-1].first,p[a][i-1].second+p[p[a][i-1].first][i-1].second};
    for(auto x:g[a]){
        dfs(x.first,a,x.second,g,p);
    }
}
int main(){
    int n,q,x,v;
    cin>>n>>q;
    vector<pair<int,int>> f(n);
    vector<vector<pair<int,int>>> g(n+1,vector<pair<int,int>>());
    vector<vector<pair<int,long long>>> par(n+1,vector<pair<int,long long>>(18));
    for(int i=0;i<n;i++){
        cin>>x>>v;
        f[i]={x,v};
    }
    stack<pair<int,int>> st;
    st.push({1e9+7,0});
    for(int i=n-1;i>=0;i--){
        while(st.top().first<=f[i].first)st.pop();
        g[st.top().second].push_back({i+1,f[i].second});

        st.push({f[i].first,i+1});
    }
    dfs(0,0,1e9+7,g,par);
    /*for(int i=0;i<=n;i++){
        cout<<i<<'\n';
        for(int j=0;j<18;j++)cout<<par[i][j].first<<' ';
        cout<<endl;
    }*/
    while(q--){
        cin>>x>>v;
        cout<<bin_lift(x,par,v)<<'\n';
    }
}

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