/*

#include <bits/stdc++.h>

using namespace std;

int main() {
    freopen("carici.in", "r", stdin);

    //freopen(".in", "r", stdin);
    //freopen(".out", "w", stdout);

    return 0;
}

 */

#include <bits/stdc++.h>

using namespace std;

#define NMAX 200002

int n, m, euler_cnt;

vector<int> graph[NMAX];

int level[NMAX];
int euler[NMAX];
int first[NMAX];

void euler_dfs(int node, int current_level) {
    euler[++euler_cnt] = node;
    level[node] = current_level;
    first[node] = euler_cnt;

    for (auto &next_node: graph[node]) {
        euler_dfs(next_node, current_level + 1);

        euler[++euler_cnt] = node;
    }
}

int rmq[18][NMAX];
int lg2[NMAX];
#define pow2(x) (1 << (x))

void rmq_create() {
    for (int i = 1; i <= euler_cnt; i++) {
        rmq[0][i] = euler[i];
    }

    lg2[0] = 1;
    for (int i = 2; i <= euler_cnt; i++) {
        lg2[i] = lg2[i / 2] + 1;
    }

    for (int i = 1; i <= lg2[euler_cnt]; i++) {
        for (int j = 1; j <= euler_cnt - pow2(i - 1); j++) {
            if (level[rmq[i - 1][j]] < level[rmq[i - 1][j + pow2(i - 1)]]) {
                rmq[i][j] = rmq[i - 1][j];
            } else {
                rmq[i][j] = rmq[i - 1][j + pow2(i - 1)];
            }

            //cout << rmq[i][j] << " ";
        }//cout << endl;
    }
}

int lca(int x, int y) {
    x = first[x];
    y = first[y];

    if (x > y) swap(x, y);

    int k = lg2[y - x + 1];
    if (level[rmq[k][x]] < level[rmq[k][y - pow2(k) + 1]]) {
        return rmq[k][x];
    }
    return rmq[k][y - pow2(k) + 1];
}

int main() {
    freopen("carici.in", "r", stdin);
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);

    scanf("%d%d", &n, &m);

    for (int i = 2, x; i <= n; i++) {
        scanf("%d", &x);
        graph[x].push_back(i);
    }

    euler_dfs(1, 0);

    /*for (int i = 1; i <= euler_cnt; i++) {
        cout << euler[i] << " ";
    } cout << endl;
    for (int i = 1; i <= n; i++) {
        cout << level[i] << " ";
    } cout << endl;*/

    rmq_create();

    for (int i = 0, x, y; i < m; i++) {
        scanf("%d%d", &x, &y);

        cout << lca(x, y) << "\n";
    }

    return 0;
}