#include <bits/stdc++.h>

#define NMAX 100005
#define LOG_NMAX 18

using namespace std;

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

int N, M, ancestor[LOG_NMAX][NMAX], level[NMAX];
vector < int > G[NMAX];

void readInput() {
    f >> N >> M;
    for (int i = 2; i <= N; ++i) {
        f >> ancestor[0][i];
        G[ancestor[0][i]].push_back(i);
    }
}

void dfs(int node, int _level) {
    level[node] = _level;

    for (auto it : G[node]) {
        dfs(it, _level + 1);
    }
}

void computeAncestors() {
    for (int k = 1; (1 << k) <= N; ++k) {
        for (int i = 1; i <= N; ++i) {
            ancestor[k][i] = ancestor[k - 1][ancestor[k - 1][i]];
        }
    }
}

int lca(int node1, int node2) {
    /*
    * Vreau ca nodul cu nivelul cel mai mare sa fie primul nod
    */
    if (level[node1] < level[node2]) {
        swap(node1, node2);
    }

    int log1, log2;
    for (log1 = 1; (1 << log1) < level[node1]; ++log1);
    for (log1 = 1; (1 << log2) < level[node2]; ++log2);

    /*
    * Urc in arbore cu primul nod pana cand ajung la acelasi nivel cu nodul 2
    */
    for (int k = log1; k >= 0; --k) {
        if (level[node1] - (1 << k) >= level[node2]) {
            node1 = ancestor[k][node1];
        }
    }

    if (node1 == node2) {
        return node1;
    }

    /*
    * Urc cu ambele noduri in arbore pana cand ajung in acelasi nod
    */
    for (int k = log2; k >= 0; --k) {
        if (ancestor[k][node1] != 0 && ancestor[k][node1] != ancestor[k][node2]) {
            node1 = ancestor[k][node1];
            node2 = ancestor[k][node2];
        }
    }

    return ancestor[0][node1];
}

void computeQueries() {
    for (int i = 1; i <= M; ++i) {
        int node1, node2;
        f >> node1 >> node2;
        g << lca(node1, node2) << '\n';
    }
}

int main() {
    readInput();
    dfs(1, 0);
    computeAncestors();
    computeQueries();
    return 0;
}