#include <fstream>
#include <vector>

using namespace std;

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

pair <int , int> rmq[20][200100];
int LOG[100100];

vector < vector < int > > gr (100100);
vector < int > lv (100100);
vector < int > pos (100100);
vector < pair<int , int> > euler;

void dfs(int root){

    euler.push_back({root , lv[root]});
    pos[root] = euler.size()-1;

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

}

int main() {

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

    //rmq

    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++){
        int dad;
        cin>>dad;
        gr[dad].push_back(i);
    }

    dfs(1);

    for (int i=0; i<euler.size(); i++){
        rmq[0][i].first = euler[i].first;
        rmq[0][i].second = euler[i].second;
    }

    for (int bit=1; bit<=LOG[n]; bit++){
        for (int i=0; i<euler.size(); i++){
            if (rmq[bit-1][i] < rmq[bit-1][i + (1 << (bit - 1))]){
                rmq[bit][i].first = rmq[bit-1][i].first;
                rmq[bit][i].second = rmq[bit-1][i].second;
            }
            else{
                rmq[bit][i].first = rmq[bit-1][i + (1 << (bit - 1))].first;
                rmq[bit][i].second = rmq[bit-1][i + (1 << (bit - 1))].second;
            }
        }
    }

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

        x = pos[x];
        y = pos[y];

        if (y < x){
            int aux = y;
            y = x;
            x = aux;
        }

        int dif = y - x + 1;

        if (rmq[LOG[dif]][x].second < rmq[LOG[dif]][y - (1 << LOG[dif]) + 1].second){
            cout<<rmq[LOG[dif]][x].first;
        }
        else{
            cout<<rmq[LOG[dif]][y - (1 << LOG[dif]) + 1].first;
        }
        cout<<'\n';

    }

    return 0;
}