#include <fstream>
#include <vector>
#include <cmath>

using namespace std;

ifstream cin ("lca.in");
ofstream cout ("lca.out");

int dp[20][100100];
int LOG[100100];

vector < vector < int > > gr (100100);
vector < int > lv (100100);

void dfs(int root){

    for (auto &x : gr[root]){
        lv[x] = lv[root] + 1;
        dfs(x);
    }

}

int main() {

    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    //stramosi

    int n , m;
    cin>>n>>m;

    for (int i=2; i<=n; i++){
        LOG[i] = LOG[i/2] + 1;
    }

    for (int i=2; i<=n; i++){
        cin>>dp[0][i];
        gr[dp[0][i]].push_back(i);
    }

    for (int bit=1; bit <= LOG[n]; bit++){
        for (int i=1; i<=n; i++){
            dp[bit][i] = dp[bit-1][dp[bit-1][i]];
        }
    }

    dfs(1);

    for (int i=1; i<=m; i++){
        int x , y;
        cin>>x>>y;

        int pos;
        //cout<<lv[x]<<" "<<lv[y]<<'\n';
        if (lv[x] > lv[y]){
            pos = lv[x] - lv[y];
            while (pos){
                x = dp[LOG[pos]][x];
                pos -= (1 << LOG[pos]);
            }
        }
        else{
            pos = lv[y] - lv[x];
            while (pos){
                y = dp[LOG[pos]][y];
                pos -= (1 << LOG[pos]);
            }
        }

        if (x == y){
            cout<<x<<'\n';
            continue;
        }

        for (int bit = LOG[lv[x]]; bit >=0; bit--){
            if (dp[bit][x] != dp[bit][y]){
                x = dp[bit][x];
                y = dp[bit][y];
            }
        }

        cout<<dp[0][x]<<'\n';

    }

    return 0;
}