#include <fstream>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int parent[18][100001],intrare[100001],iesire[100001],cnt = 0;
vector <int> muchii[100001];
bool viz[100001];
void dfs(int nod){
    viz[nod] = 1;
    int i;
    cnt++;
    intrare[nod] = cnt;
    for(i = 0;i < muchii[nod].size();i++){
        int vecin = muchii[nod][i];
        if(!viz[vecin]){
            dfs(vecin);
        }
    }
    iesire[nod] = cnt;
}
int main()
{
    int n,m,i,j;
    cin >> n >> m;
    for(i = 2;i <= n;i++){
        cin >> parent[0][i];
        muchii[i].push_back(parent[0][i]);
        muchii[parent[0][i]].push_back(i);
    }
    for(i = 1;(1 << i) <= n;i++){
        for(j = 2;j <= n;j++){
            parent[i][j] = parent[i-1][parent[i-1][j]];
        }
    }
    //cout << parent[0][3] << " ";
    dfs(1);
    int a,b;
    for(i = 1;i <= m;i++){
    cin >> a >> b;
        //int pas = 1 << 17;
        int sol = 0,r = a;
        int pas = 17;
        while(pas >= 0){
              if(parent[pas][r] >= 1 && parent[pas][r] <= n && !(intrare[parent[pas][r]] < intrare[b] && iesire[parent[pas][r]] >= iesire[b]))
                 r = parent[pas][r];
            pas--;
        }
        //cout << r << " ";

         if((intrare[a] < intrare[b] && iesire[a] >= iesire[b])){
            cout << a << "\n";
        }else if((intrare[b] < intrare[a] && iesire[b] >= iesire[a])){
             cout << b << "\n";
        }else if(a!=b){
            cout << parent[0][r] << "\n";
        }else{
        cout << b << "\n";}
    }
    return 0;
}