#include <fstream>
#include <vector>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");

int n, m;
int anc[50][int(1e5) + 5];
int lg2[int(1e5) + 5];
int level[int(1e5) + 5];
vector<int> vecini[int(1e5) + 5];

void dfs(int node, int tata){
    level[node] = level[tata] + 1;

    for (int vec: vecini[node]){
        dfs(vec, node);
    }
}
int main(){

    fin >> n >> m;
    anc[0][1] = 1;

    for (int i = 2; i <= n; i++){
        lg2[i] = lg2[i / 2] + 1;
    }

    level[1] = 0;

    for (int i = 2; i <= n; i++){
        fin >> anc[0][i];
        vecini[anc[0][i]].push_back(i);
    }

    dfs(1, 0);

    for (int exp = 1; exp <= lg2[n]; exp++){
        for (int i = 1; i <= n; i++){
            anc[exp][i] = anc[exp - 1][anc[exp - 1][i]];
        }
    }

    for (int i = 1; i <= m; i++){
        int a, b;
        fin >> a >> b;
        if (level[a] < level[b])
            swap(a, b);

        int level_diff = abs(level[a] - level[b]);

        if (level_diff) {
            for (int exp = lg2[level_diff]; exp >= 0; exp--) {
                if ((1 << exp) <= level_diff) {
                    a = anc[exp][a];
                    level_diff -= (1 << exp);
                }
            }
        }

        int max_level = level[b];
        int lca_dist = 0;

        for (int exp = lg2[max_level]; exp >= 0; exp --){

            if (anc[exp][a] != anc[exp][b]){

                lca_dist += (1 << exp);
                a = anc[lca_dist][a];
                b = anc[lca_dist][b];

            }

        }

        if (a == b)
            fout << a << '\n';
        else
            fout << anc[0][a] << '\n';

    }

    return 0;
}