#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast")

using namespace std;

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

const int MAX_N = 100005;
int n, parent, q, x, y, lft, rgt, pw2;
vector <int> leaves[MAX_N];

int m, euler[2 * MAX_N], level[2 * MAX_N], first[MAX_N], lg2[2 * MAX_N], rmq[18][2 * MAX_N];
void dfs_euler(int nod, int lvl){
    m++;
    euler[m] = nod;
    level[m] = lvl;
    first[nod] = m;
    for(auto leaf : leaves[nod]){
        dfs_euler(leaf, lvl+1);
        m++;
        euler[m] = nod;
        level[m] = lvl;
    }
}

int main (){
    ios_base::sync_with_stdio(false);
    fin.tie(nullptr), fout.tie(nullptr);

    fin>>n>>q;
    for(int i=2; i<=n; i++){
        fin>>parent;
        leaves[parent].push_back(i);
    }

    dfs_euler(1, 1);

    for(int i=2; i<=m; i++)
        lg2[i] = lg2[i>>1] + 1;

    for(int j=1; j<=m; j++)
        rmq[0][j] = j;

    for(int i=1; i<=lg2[m]; i++)
        for(int j=1, jj; (jj = j + (1 << (i-1)))<=m; j++)
            if(level[ rmq[i-1][j] ] < level[ rmq[i-1][jj] ])
                rmq[i][j] = rmq[i-1][j];
            else
                rmq[i][j] = rmq[i-1][jj];

    while(q--){
        fin>>x>>y;
        lft = min(first[x], first[y]);
        rgt = max(first[x], first[y]);
        pw2 = lg2[rgt-lft+1];
        x = rmq[pw2][lft];
        y = rmq[pw2][rgt-(1 << pw2)+1];
        if(level[x] < level[y])
            fout<<euler[x]<<"\n";
        else
            fout<<euler[y]<<"\n";
    }
    return 0;
}