Cod sursa(job #2154401)

Utilizator dumitrescu_andreiDumitrescu Andrei dumitrescu_andrei Data 6 martie 2018 22:10:57
Problema Lowest Common Ancestor Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 0.7 kb
#include <bits/stdc++.h>
using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

int n,m,tata[100005],levels[100005];
vector <int> V[100005];

void DFS(int x)
{
    for(int i=0; i<V[x].size(); ++i)
    {
        levels[V[x][i]]=levels[x]+1;
        DFS(V[x][i]);
    }

}

int main()
{
    f>>n>>m;
    for(int i=2; i<=n; ++i)
    {
        f>>tata[i];
        V[tata[i]].push_back(i);
    }
    levels[1]=1;
    DFS(1);
    for(int i=1; i<=m; ++i)
    {
        int x,y;
        f>>x>>y;
        while(x!=y)
        {
            if(levels[x]>levels[y])
                x=tata[x];
            else
                y=tata[y];
        }
        g<<x<<'\n';
    }
}