#include <fstream>
#include <iostream>
#include <vector>

using namespace std;

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

const int nmax = 100005;
int eul[2*nmax], ne, n, m, tt, x, y, i, j, first[nmax];
int rmq[18][2*nmax], niv[nmax], log2[2*nmax];
vector <int> ls[nmax];

void dfs(int x) {
    int l = ls[x].size(), i, y;
    eul[++ne] = x;
    first[x] = ne;

    for (i = 0; i < l; i++) {
        y = ls[x][i];
        niv[y] = niv[x] + 1;
        dfs(y);
        eul[++ne] = x;
    }
}

void range_minimum() {
    int i, j, x, y;

    for (i = 2; i <= ne; i++)
        log2[i] = log2[i/2]+1;

    for (i = 1; i <= ne; i++)
        rmq[0][i] = eul[i];

    for (i = 1; (1 << i) <= ne; i++)
        for (j = 1; j + (1 << i) - 1 <= ne; j++) {
            x = rmq[i-1][j];
            y = rmq[i-1][j + (1 << (i-1))];
            if (niv[x] < niv[y])
                rmq[i][j] = x;
            else
                rmq[i][j] = y;
        }
}

int query(int x, int y) {
    int a = first[x], b = first[y];
    if (a > b) swap(a, b);
    int diff = b-a+1;
    int i = log2[diff];
    int aa = rmq[i][a];
    int bb = rmq[i][b - (1 << i) + 1];

    if (niv[aa] < niv[bb])
        return aa;
    else return bb;
}

int main() {
    f >> n >> m;
    for (i = 2; i <= n; i++) {
        f >> tt;
        ls[tt].push_back(i);
    }

    dfs(1);
    range_minimum();

    while (m--) {
        f >> x >> y;
        g << query(x, y) << '\n';
    }
}