#include <iostream>
#include <fstream>
#include <map>
#include <string.h>
#include <string>
#include <vector>
#include <set>
#include <math.h>
#include <algorithm>
#include <iomanip>

using namespace std;

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

int n,m;

int dp[100000][19];
int l[100000];

int geta(int a, int x)
{
    int t = a;
    int i=0;
    while (x)
    {
        if (x & (1<<i))
        {
            x = x^(1<<i);
            t = dp[t][i];
        }
        i++;
    }
    return t;
}

int process(int x, int y)
{
    if ( l[x]>l[y] )
    {
        int d = l[x]-l[y];
        x = geta(x,d);
    }
    else if (l[x] < l[y])
    {
        int d = l[y]-l[x];
        y = geta(y,d);
    }

    if (x==y) return x;

    int ll = 0,rr = log2(l[x])+1;
    while (ll<rr)
    {
        int mm = (ll+rr)/2 + (ll+rr)%2;
        if (dp[x][mm] != dp[y][mm])
            ll=mm;
        else rr=mm-1;
    }

    x = dp[x][ll];
    y = dp[y][ll];
    return process(x,y);
}

int main()
{
    fin>>n>>m;

    dp[0][0] = 0;
    l[0]=0;

    for (int i=1; i<n; i++)
    {
        fin>>dp[i][0];
        dp[i][0]--;
        l[i] = l [ dp[i][0] ]+1;
        for (int j=1; (1<<(j-1)) <= l[i] ; j++)
            dp[i][j] = dp[dp[i][j-1]][j-1];
    }

    for (int i=0; i<m; i++)
    {
        int x,y;
        fin>>x>>y;
        x--;
        y--;
        fout<<process(x,y)+1<<'\n';
    }
    return 0;
}