#include <fstream>
#include <vector>
#define NMAX 100005
#define LOG 18
using namespace std;
ifstream  fin("lca.in");
ofstream fout("lca.out");
int N,M,poz,tata[NMAX],nivel[NMAX];
int first[NMAX],euler[NMAX],rmq[NMAX][LOG];
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 nod)
{
    euler[++poz]=nod;
    first[nod]=poz;
    for(int i=0; i<tree[nod].size(); i++)
    {
        int next_nod=tree[nod][i];
        nivel[next_nod]=nivel[nod]+1;

        DFS(next_nod);
        euler[++poz]=nod;
    }
}

int main()
{
    citire();

    poz=0;
    DFS(1);

    int a,b;
    for(int q=1; q<=M; q++)
    {
        fin>>a>>b;

        int vmin,ans;
        ans=vmin=NMAX;
        for(int i=min(first[a],first[b]); i<=max(first[a],first[b]); i++)
        {
            if(nivel[euler[i]]<vmin)
            {
                vmin=nivel[euler[i]];
                ans=euler[i];
            }
        }

        fout<< ans << "\n";
    }

    return 0;
}