#include <iostream>
#include <fstream>
#include <vector>
#include <cmath>
using namespace std;

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

const int NMAX = 1e5 + 1; 
const int logNMAX = 41;

vector<int> fii[NMAX];
vector<int> euler, nivele, poz(NMAX);

int n, m;
int rmq[2 * NMAX][logNMAX];

void calculeazaMat(int n) {
    for (int i = 0; i < n; i++) {
        rmq[i][0] = i;
    }
    for (int j = 1; j <= log2(n); j++) {
        for (int i = 0; i + (1 << j) <= n; i++) {
            // rmq[i][j] = min(rmq[i][j - 1], rmq[i + (1 << (j - 1))][j - 1]);
            if (nivele[rmq[i][j - 1]] < nivele[rmq[i + (1 << (j - 1))][j - 1]]) {
                rmq[i][j] = rmq[i][j - 1];
            }
            else {
                rmq[i][j] = rmq[i + (1 << (j - 1))][j - 1];
            }
        }
    }
}

int query(int i, int j) {
    if (i > j) {
        swap(i, j);
    }
    int k = log2(j - i + 1);
    return euler[nivele[rmq[i][k]] < nivele[rmq[j - (1 << k) + 1][k]] ? rmq[i][k] : rmq[j - (1 << k) + 1][k]];
}

void dfs(int node, int h) {
    euler.push_back(node);
    nivele.push_back(h);
    poz[node] = euler.size() - 1;
    for (const auto& i : fii[node]) {
        dfs(i, h + 1);
        euler.push_back(node);
        nivele.push_back(h);
    } 
}

int main() {
    fin >> n >> m;
    for (int i = 2; i <= n; i++) {
        int x;
        fin >> x;
        fii[x].push_back(i);
    }
    dfs(1, 0);

    // for (auto i: euler) cout << i << " ";
    // cout << "\n";
    // for (auto i: nivele) cout << i << " ";
    
    calculeazaMat(euler.size());

    for (int i = 0; i < m; i++) {
        int x, y;
        fin >> x >> y;
        fout << query(poz[x], poz[y]) << "\n";
    }


}