#include <iostream>
#include <fstream>

using namespace std;

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

const int N = 100001;
const int M = 100001;
const int L = 18;
int n, m, nr, time1, vf[N], urm[N], lst[N], t[L][N], tb[N], to[N];

void add(int x, int y)
{
    vf[++nr] = y;
    urm[nr] = lst[x];
    lst[x] = nr;
}

void dfs(int x)
{
    tb[x] = ++time1;
    int y;
    for (int p = lst[x]; p != 0; p = urm[p])
    {
        y = vf[p];
        if (tb[y] == 0)
        {
            dfs(y);
            t[0][y] = x;
        }
    }
    to[x] = ++time1;
}

int lca(int x, int y)
{
    if(tb[x]<=tb[y] && to[y]<=to[x])
    {
        return x;
    }
    int pas = L - 1;
    int s;
    while (pas >= 0)
    {
        s = t[pas][x];
        if (s != 0 && ((tb[s] > tb[y]) || (to[s] < to[y])))
            x = s;
        pas--;
    }
    return t[0][x];
}

int main()
{
    fin >> n >> m;
    for (int i = 2; i <= n; i++)
    {
        int a;
        fin >> a;
        add(a, i);
    }
    dfs(1);
    for (int i = 1; (1 << i) <= n; i++)
        for (int j = 1; j <= n; j++)
            t[i][j] = t[i - 1][t[i - 1][j]];
    for (int i = 1; i <= m; i++)
    {
        int x, y;
        fin >> x >> y;
        fout << lca(x, y) << '\n';
    }
    fin.close();
    fout.close();
    return 0;
}