#include <fstream>
#include <vector>
#include <cstdlib>
#include <ctime>

#define pi pair<int, int>
#define mp make_pair
#define pb push_back

using namespace std;

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

const int N = 100100;
const int M = 2000010;

int f[N], true_f[N];
bool marked[N];
vector<int> g[N];
vector<pi> query[N];
int qans[M];

int _find(int x) {
   if(x != f[x]) {
      f[x] = _find(f[x]);
   }
   return f[x];
}

void _merge(int x, int y) {
   int rx = _find(x), ry = _find(y);
   if(rand() & 1) {
      f[rx] = ry;
   }
   else {
      f[ry] = rx;
   }
}

void offlineLca(int x) {
   f[x] = x;
   true_f[x] = x;
   for(int y : g[x]) {
      offlineLca(y);
      _merge(x, y);
      true_f[_find(x)] = x;
   }
   marked[x] = 1;
   for(auto q : query[x]) {
      if(marked[q.first]) {
         qans[q.second] = true_f[_find(q.first)];
      }
   }
}

int main() {
   int n, m, i, x, y;

   in >> n >> m;
   for(i = 2; i <= n; i++) {
      in >> x;
      g[x].pb(i);
   }
   for(i = 1; i <= m; i++) {
      in >> x >> y;
      query[x].pb(mp(y, i));
      query[y].pb(mp(x, i));
   }

   offlineLca(1);
   for(i = 1; i <= m; i++) {
      out << qans[i] << '\n';
   }
}