#include <bits/stdc++.h>

using namespace std;

ifstream fin ("lca.in");
ofstream fout ("lca.out");

const int nMax = 100010, lgg = int(log2(nMax)) + 2;

int n, m, i, j, x, y, E, lg;
int e[2*nMax], first[nMax], niv[nMax], rmq[nMax][lgg];

vector <int> v[nMax];

void euler(int nod, int k)
{
    e[++E] = nod;
    first[nod] = E;
    niv[nod] = k;

    for(auto it : v[nod])
    {
        euler(it, k+1);
        e[++E] = nod;
    }
}

void build_rmq()
{
    for(i=1; i<=E; i++)
        rmq[i][0] = e[i];
    lg = log2(E) + 1;
    for(j=1; j<=lg+1; j++)
        for(i=1; i<=E-(1<<j)+1; i++)
        {
            if(niv[rmq[i][j-1]] <= niv[rmq[i+(1<<(j-1))][j-1]])
                rmq[i][j] = rmq[i][j-1];
            else rmq[i][j] = rmq[i+(1<<(j-1))][j-1];
        }
}

int rmq_query(int a, int b)
{
    if(a > b) swap(a, b);
    int X = int(log2(b-a+1));
    if(niv[rmq[a][X]] <=  niv[rmq[b-(1<<X)+1][X]])
        return rmq[a][X];
    else return rmq[b-(1<<X)+1][X];
}

void solve()
{
    for(i=1; i<=m; i++)
    {
        fin >> x >> y;
        fout << rmq_query(first[x], first[y]) << '\n';
    }
}

int main()
{
    fin >> n >> m;
    for(i=2; i<=n; i++)
    {
        fin >> x;
        v[x].push_back(i);
    }
    euler(1, 1);
    build_rmq();
    solve();
    return 0;
}