Cod sursa(job #2445985)

Utilizator CharacterMeCharacter Me CharacterMe Data 6 august 2019 16:36:10
Problema Stramosi Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.16 kb
#include <iostream>
#include <cstdio>
#include <vector>
using namespace std;
///variables
int n, m, i, out[300001];
vector<int> graph[250001];
vector<int> v, rad;
vector<pair<int, int> > query[250001];
///functions
void read();
void solve();
void dfs(int node);
void write();
int main()
{
    read();
    solve();
    write();
    return 0;
}
void read(){
    freopen("stramosi.in", "r", stdin);
    scanf("%d%d", &n, &m);
    for(i=1; i<=n; ++i){
        int head;
        scanf("%d", &head);
        if(head) graph[head].push_back(i);
        else rad.push_back(i);
    }
    for(i=1; i<=m; ++i){
        int node, p;
        scanf("%d%d", &node, &p);
        query[node].push_back({p, i});
    }
    return;
}
void solve(){
    for(auto j:rad) dfs(j);
    return;
}
void write(){
    freopen("stramosi.out", "w", stdout);
    for(i=1; i<=m; ++i) printf("%d\n", out[i]);
    return;
}
void dfs(int node){
    for(auto i:query[node]){
        if(i.first<=v.size()) out[i.second]=v[v.size()-i.first];
        else out[i.second]=0;
    }
    v.push_back(node);
    for(auto i:graph[node]) dfs(i);
    v.pop_back();
    return;
}