#include <bits/stdc++.h>

using namespace std;

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

int n, q;
const int nmax = 200005;
vector <int> l[100005];
struct numar
{
    int nod,niv;
} rmq[19][nmax];

int e[nmax], p_curent, p_start[nmax];

void dfs(int nod, int niv)
{
    rmq[0][++p_curent] = {nod, niv};
    p_start[nod] = p_curent;
    for(int i = 0; i < l[nod].size(); i++)
    {
        int vecin = l[nod][i];
        dfs(vecin, niv+1);
        rmq[0][++p_curent] = {nod,niv};
    }
}
int lca(int x, int y)
{
  int pos_x = p_start[x];
  int pos_y = p_start[y];
  if(pos_x > pos_y)
    swap(pos_x, pos_y);
  int p = e[pos_y - pos_x + 1];
  numar st = rmq[p][pos_x];
  numar dr = rmq[p][pos_y - (1 << p) + 1];
  if(st.niv < dr.niv)
    return st.nod;
  else
    return dr.nod;
}
int main()
{
    f >> n >> q;
    for(int i = 2; i <= n; i++)
    {
        int x;
        f >> x;
        l[x].push_back(i);
    }
    p_curent = 0;
    dfs(1, 1);
    e[1] = 0;
    for(int i = 2; i <= p_curent; i++)
        e[i] = e[i / 2] + 1;
    for(int p = 1; (1 << p) <= p_curent; p++)
        for(int i = 1; i <= p_curent; i++)
        {
            numar st = rmq[p-1][i];
            if(i + (1 << (p - 1)) <= p_curent)
            {
              numar dr = rmq[p-1][i + (1 << (p - 1))];
              if(st.niv < dr.niv)
                rmq[p][i] = st;
              else
                rmq[p][i] = dr;
            }
            else
              rmq[p][i] = st;
        }
    while(q--)
    {
        int x, y;
        f >> x >> y;
        g << lca(x, y)<< "\n";
    }
    return 0;
}