Cod sursa(job #3344800)

Utilizator Gabriel_DaescuDaescu Gabriel Florin Gabriel_Daescu Data 5 martie 2026 19:33:26
Problema Lowest Common Ancestor Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.95 kb
#include <fstream>
#include <vector>
#define NMAX 10005
using namespace std;
ifstream  fin("lca.in");
ofstream fout("lca.out");
int n,m,tata[NMAX],nivel[NMAX];
vector<int> tree[NMAX];

void citire()
{
    fin>>n>>m;

    for(int i=2; i<=n; i++)
    {
        fin>>tata[i];
        tree[tata[i]].push_back(i);
    }
}

void DFS(int parent, int nod)
{
    nivel[nod]=nivel[parent]+1;

    for(int i=0; i<tree[nod].size(); i++)
    {
        int next_nod=tree[nod][i];
        if(next_nod!=parent)
        {
            DFS(nod,next_nod);
        }
    }
}

int lca(int x, int y)
{
    while(x!=y)
    {
        if(nivel[x]>=nivel[y])
        {
            x=tata[x];
        }
        else
        {
            y=tata[y];
        }
    }
}

int main()
{
    citire();

    DFS(0,1);

    int a,b;
    for(int i=1; i<=m; i++)
    {
        fin>>a>>b;
        fout<< lca(a,b) << "\n";
    }

    return 0;
}