#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
const int NMAX = 100000;
vector <int> G[NMAX + 5];
int e[2 * NMAX + 5] , h[NMAX + 5] , l[2 * NMAX + 5] , d[2 * NMAX + 5][25] , lg;
void dfs(int u , int lvl)
{
    int v , j;
    lg ++;
    e[lg] = u;
    l[lg] = lvl;
    if(h[u] == -1)
        h[u] = lg;
    for(j = 0 ; j < G[u].size() ; j ++)
    {
        v = G[u][j];
        dfs(v , lvl + 1);
        lg ++;
        e[lg] = u;
        l[lg] = lvl;
    }
}
void dinamica()
{
    int i , j;
    for(i = 1 ; i <= lg ; i ++)
        d[i][0] = i;
    for(j = 1 ; (1 << j) <= lg ; j ++)
        for(i = 1 ; i + (1 << j) - 1 <= lg ; i ++)
            if(l[d[i][j - 1]] < l[d[i + (1 << (j - 1))][j - 1]])
                d[i][j] = d[i][j - 1];
            else
                d[i][j] = d[i + (1 << (j - 1))][j - 1];
}
int rmq(int x , int y)
{
    int j;
    j = 0;
    while((1 << j) <= y - x + 1)
        j ++;
    j --;
    if(l[d[x][j]] <= l[d[y - (1 << j) + 1][j]])
        return d[x][j];
    return d[y - (1 << j) + 1][j];
}
int main()
{
    freopen("lca.in" , "r" , stdin);
    freopen("lca.out" , "w" , stdout);
    int n , m , i , x , y;
    scanf("%d%d" , &n , &m);
    for(y = 2 ; y <= n ; y ++)
    {
        scanf("%d" , &x);
        G[x].push_back(y);
        h[y] = -1;
    }
    h[1] = -1;
    dfs(1 , 1);
    dinamica();
    for(i = 1 ; i <= m ; i ++)
    {
        scanf("%d%d" , &x , &y);
        printf("%d\n" , e[rmq(min(h[x] , h[y]) , max(h[x] , h[y]))]);
    }
    return 0;
}