#include <bits/stdc++.h>
#define nmax 100005
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");

int n, m;
vector <int> graph[nmax];
int euler[3*nmax], lungime_euler, indice_euler;
int euler_valoare[nmax], valoare_euler[nmax], LOG2s[3*nmax], first[nmax];
int rmq[nmax*3][24];

void citire()
{
    int i, x;
    fin >> n >> m;
    for(i = 2; i <= n; i++)
        fin >> x, graph[x].push_back(i);
    LOG2s[1] = 0;
    for(i = 2; i <= 3*nmax; i++)
        LOG2s[i] = LOG2s[i >> 1] + 1;
}

void reprezentare_euler(int nod)
{
    unsigned i, len;
    len = graph[nod].size();
    first[nod] = lungime_euler;
    valoare_euler[nod] = indice_euler;
    euler_valoare[indice_euler] = nod;
    euler[lungime_euler] = indice_euler, lungime_euler+=1, indice_euler+=1;
    for(i = 0; i < len; i++)
    {
        reprezentare_euler(graph[nod][i]);
        euler[lungime_euler] = valoare_euler[nod], lungime_euler+=1;
    }
}

void sparse_table()
{
    int i, j, z, t;
    for(i = 0; i < lungime_euler; i++)
        rmq[i][0] = euler[i];
    for(j = 1; j <= LOG2s[lungime_euler]; j++)
    {

        t = (1 << (j - 1)), z = (1 << j);
        for(i = 0; i + z <= lungime_euler; i++)
            rmq[i][j] = valoare_euler[min(euler_valoare[rmq[i + t][j - 1]], euler_valoare[rmq[i][j - 1]])];
    }
}

int solve(int a, int b)
{
    int k;
    a = first[a], b = first[b];
    if(a > b)
    swap(a, b);
    k = LOG2s[b-a];
    return (rmq[a][k] < rmq[b - (1 << k) + 1][k]) ? euler_valoare[rmq[a][k]] :  euler_valoare[rmq[b - (1 << k) + 1][k]];
}

int main()
{
    int i, x, y;
    citire();
    reprezentare_euler(1);
    sparse_table();
    for(i = 0; i < m; i++)
    {
        fin >> x >> y;
        fout << solve(x, y) << '\n';
    }
    return 0;
}