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

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

vector<int> eul, l, g[100005];
int first[100005], k, n, m;
int logg[200010], rmq[20][400020];

void citire() {
    fin >> n >> m;
    for(int i = 2; i <= n; i++) {
        int x;
        fin >> x;
        g[x].push_back(i);
    }
}

void dfs(int x, int level) {
    eul.push_back(x);
    l.push_back(level);
    first[x] = eul.size()-1;
    for(auto next: g[x]) {
        dfs(next, level+1);
        eul.push_back(x);
        l.push_back(level);
    }
}

void RMQ() {
    int k = eul.size();
    for(int i = 2; i <= k; i++)
        logg[i] = logg[i/2]+1;

    for(int i = 0; i <= k; i++)
        rmq[0][i] = i;

    for(int i = 1; (1<<i) <= k; i++)
        for(int j = 0; j+(1<<i)-1 < k; j++) {
            rmq[i][j] = rmq[i-1][j];
            if(l[rmq[i-1][j+(1<<(i-1))]] < l[rmq[i][j]])
               rmq[i][j] = rmq[i-1][j+(1<<(i-1))];
        }
}

int lca(int x, int y) {
    int dif = abs(first[y]-first[x])+1;
    int lg = logg[dif];
    int res = rmq[lg][min(first[y], first[x])];
    if(l[res] > l[rmq[lg][max(first[y], first[x])-(1<<lg)]])
        res = rmq[lg][min(first[y], first[x])+dif-(1<<lg)];
    return eul[res];
}

int main() {
    citire();
    dfs(1, 0);
    RMQ();

    while(m--) {
        int x, y;
        fin >> x >> y;
        fout << lca(x, y) << '\n';
    }
}