#include <bits/stdc++.h>
#define dim 100002
using namespace std;

ifstream in("lca.in");
ofstream out("lca.out");
vector<int> v[dim];
int euler[dim << 1], l[dim << 1], lg[dim << 1], f[dim], rmq[dim << 1][20], k;

void dfs(int num, int lev)
{
    euler[++k] = num;
    l[k] = lev;
    f[num] = k;
    for (int i = 0; i < v[num].size(); i++)
    {
        dfs(v[num][i], lev + 1);
        euler[++k] = num;
        l[k] = lev;
    }
}

int main()
{
    int n, m, x;
    in >> n >> m;
    for(int i = 2; i <= n; i++)
    {
        in >> x;
        v[x].push_back(i);
    }
    dfs(1, 0);

    for(int i = 2; i <= k; i ++)
        lg[i] = lg[i >> 1] + 1, rmq[i][0] = i;
    rmq[1][0] = 1;

    for (int j = 0; j <= lg[k]; j++)
        for (int i = 0; i + (1 << j) <= k; i++)
            if (l[rmq[i][j]] > l[rmq[i + (1 << j)][j]])
                rmq[i][j + 1] = rmq[i + (1 << j)][j];
            else
                rmq[i][j + 1] = rmq[i][j];

    while (m--)
    {
        int i, j;
        in >> i >> j;
        i = f[i];
        j = f[j];
        if (i > j)
            swap(i, j);
        int num = lg[j - i + 1];
        if (l[rmq[i][num]] > l[rmq[j - (1 << num) + 1][num]])
            out << euler[rmq[j - (1 << num) + 1][num]] << "\n";
        else
            out << euler[rmq[i][num]] << "\n";
    }
    return 0;
}