#include <fstream>

using namespace std;

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

const int L = 17, N = 2 * 100001, M = 4 * 100001, E = 2*N - 1;

int n, m, rmq[L][N], vf[M], urm[M], lst[M], log2[N], nr, ne, prima[N], e[E], nivel[N];

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

void dfs(int x)
{
    e[++ne] = x;
    prima[x] = ne;
    for(int p = lst[x]; p != 0; p = urm[p])
    {
        int y = vf[p];
        if(prima[y] == 0)
            nivel[y] = 1 + nivel[x], dfs(y), e[++ne] = x;
    }
}

int lca(int x, int y)
{
    int px = prima[x];
    int py = prima[y];

    if(px > py)
    {
        swap(px, py);
    }
    int l = log2[py - px + 1];
    int rez = rmq[l][px + (1 << l) - 1];
    if(nivel[rmq[l][py]] < nivel[rez])
        rez = rmq[l][py];
    return rez;
}

int main()
{
    in >> n >> m;
    for(int i = 2, x; i <= n; i++)
    {
        in >> x;
        adauga(x, i);
       //adauga(i, x);
    }
    log2[1] = 0;
    for(int i = 2; i <= 2*n; i++)
        log2[i] = 1 + log2[i/2];
    dfs(1);
    for(int j = 1; j <= ne; j++)\
    {
        rmq[0][j] = e[j];
    }
    for(int i = 1; i < L; i++)
    {
        for(int j = 1 << i; j < 2*n; j++)
        {
            rmq[i][j] = rmq[i - 1][j];

            int x = rmq[i-1][j - (1 << (i-1))];
            if(nivel[x] < nivel[rmq[i][j]])
            {
                rmq[i][j] = x;
            }
        }
    }
    for(int i = 1, x, y; i <= m; i++)
    {
        in >> x >> y;
        out << lca(x, y) << "\n";
    }
    return 0;
}