#include <bits/stdc++.h>

using namespace std;

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

const int kN = 2e5 + 5;

vector<int>g[kN];
int n, q;
int euler[kN], first[kN], level[kN], len;
int rmq[kN][20], lg[kN];

void dfs (int nod, int dad = -1, int h = 1){
   euler[++len] = nod;
   level[len] = h;
   first[nod] = len;
   for (int u : g[nod]){
      if (u == dad){
         continue;
      }
      dfs(u, nod, h + 1);
      euler[++len] = nod;
      level[len] = h;
   }
}

void precalc (){
   for (int i = 2; i < kN; i++){
      lg[i] = 1 + lg[i / 2];
   }
   for (int i = 1; i <= len; i++){
      rmq[i][0] = i;
   }
   for (int j = 1; j < 20; j++){
      for (int i = 1; i + (1 << j) <= len; i++){
         rmq[i][j] = rmq[i][j - 1];
         if (level[rmq[i][j]] > level[rmq[i + (1 << (j - 1))][j - 1]]){
            rmq[i][j] = rmq[i + (1 << (j - 1))][j - 1];
         }
      }
   }
}

int lca (int x, int y){
   x = first[x], y = first[y];
   if (x > y){
      swap(x, y);
   }
   int k = lg[y - x + 1];
   int ans = rmq[x][k];
   if (level[ans] > level[rmq[y - (1 << k) + 1][k]]){
      ans = rmq[y - (1 << k) + 1][k];
   }
   return euler[ans];
}

int main(){
   ios_base::sync_with_stdio(false);

   fin >> n >> q;
   for (int i = 2; i <= n; i++){
      int x; fin >> x;
      g[x].push_back(i);
   }
   dfs(1);
   precalc();
   while (q--){
      int x, y; fin >> x >> y;
      fout << lca(x, y) << '\n';
   }
}