#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <vector>
using namespace std;


#define nmax 200010
#define pb push_back

int Euler[nmax], First[nmax], L[nmax], N, M, RMQ[nmax][20], X, Y, K;
vector<int> G[nmax];


void DFS(int node, int level)
{
     Euler[++ K] = node;
     L[K] = level;
     First[node] = K;
     for(vector<int> :: iterator it = G[node].begin(); it != G[node].end(); ++ it)
     {
                     DFS(*it, level + 1);
                     Euler[++ K] = node;
                     L[K] = level;
     }
}


void RangeMinimumQuery()
{
     int i, j;
     for(i = 0; i < K; i++) RMQ[i][0] = i;
     for(j = 1; (1 << j) <= K; j ++)
     {
           for(i = 0; i + (1 << j) - 1 < K; i++)
           {
                 if(L[ RMQ[i][j - 1] ] < L[ RMQ[i + (1 << (j - 1))][j - 1] ])
                       RMQ[i][j] = RMQ[i][j - 1];
                 else 
                      RMQ[i][j] = RMQ[i + (1 << (j - 1))][j - 1];
           }
     }
}

int LCA(int A, int B)
{
     int i, j, k;
     i = First[A];
     j = First[B];
     if(i > j) i ^= j ^= i ^= j;
     k = (int) log2(j - i + 1);
     if(Euler[ RMQ[i][k] ] <= Euler[ RMQ[j - (1 << k) + 1][k] ]) return Euler[ RMQ[i][k] ];
     else return Euler[ RMQ[j - (1 << k) + 1][k] ];
}

int main()
{
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);
    int i;
    scanf("%i %i", &N, &M);
    for(i = 2; i <= N; i++)
    {
          scanf("%i", &X);
          G[X].pb(i);
    }
    K = -1;
    DFS(1, 0);
    K ++;
    RangeMinimumQuery();
    for(; M; M --)
    {
          scanf("%i %i", &X, &Y);
          printf("%i\n", LCA(X, Y));
    }
    return 0;
}