#include <iostream>
#include <fstream>
#include <vector>
#define NMAX 100002
#define LMAX 18
using namespace std;
vector<int> v[NMAX];
int n,m,x,y,up[NMAX][LMAX],dp[NMAX];

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

void dfs(int nod){
    for(auto vecin: v[nod]){
        up[vecin][0] = nod;
        dp[vecin] = dp[nod]+1;
        for(int j = 1; j < LMAX; j++){
            up[vecin][j] = up[up[vecin][j-1]][j-1];
        }
        dfs(vecin);
    }
}

int lca(int a, int b){
    if(dp[a] < dp[b]){
        swap(a, b);
    }
    int k = dp[a]-dp[b];
    for(int j = LMAX-1; j >= 0; j--){
        if(k & (1<<j)){
            a = up[a][j];
        }
    }
    if(a == b){
        return a;
    }
    for(int j = LMAX-1; j >= 0; j--){
        if(up[a][j] != up[b][j]){
            a = up[a][j];
            b = up[b][j];
        }
    }
    return up[a][0];
}

int main()
{
    fin >> n >> m;
    for(int i = 2; i <= n; i++){
        fin >> x;
        if(x != i){
            v[x].push_back(i);
        }
    }
    dp[1] = 1;
    dfs(1);
    for(int i = 1; i <= m; i++){
        fin >> x >> y;
        fout << lca(x, y) << "\n";
    }
    return 0;
}