#include <bits/stdc++.h>

#define N 100000 + 5 

using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n, m, pos;
int t[N], heavy[N], position[N], seq[N], size[N], level[N];
vector<int> graf[N];

void read() {
  f>>n>>m;
  for(int i = 2;i <= n;++i) {
    f>>t[i];
    graf[i].push_back(t[i]);
    graf[t[i]].push_back(i);
  }
}

void dfs(int node, int parent) {
  level[node] = level[parent] + 1;
  size[node] = 1;

  int maximum = 0;
  for(const auto& vecin : graf[node]) {
    if(vecin != t[node]) {
      dfs(vecin, node);
      size[node] += size[vecin];

      if(maximum < size[node]) {
        heavy[node] = vecin; 
        maximum = size[vecin];
      }
    }
  }
}

void decomposition(int node, int superior) {
  seq[node] = superior;
  position[node] = ++pos;

  if(heavy[node]) {
    decomposition(heavy[node], superior);
  }
  for(const auto& vecin : graf[node]) {
    if(vecin != t[node] && vecin != heavy[node]) {
      decomposition(vecin, vecin);
    }
  }
}


int lca(int x, int y) {
  while(seq[x] != seq[y]) {
    if(position[seq[x]] < position[seq[y]]) {
      x = x ^ y;
      y = x ^ y;
      x = x ^ y;
    }
    x = t[seq[x]];
  }
  if(level[x] < level[y]) {
    return x;
  }
  return y;
}

void solve() {
  dfs(1, 0);
  decomposition(1, 1);
  int x, y;
  for(int i = 1;i <= m;++i) {
    f>>x>>y;
    g<<lca(x, y)<<'\n';
  }
}

int main() {
  read();
  solve();
  return 0;
}