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

#define nmax 200010

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


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

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 = First[A], j = First[B], k;
    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, j;
    scanf("%i %i", &N, &M);
    for(i = 2; i <= N; i++)
    {
          scanf("%i", &X);
          G[X].push_back(i);
    }
    K = -1;
    DFS(1, 0);
    K ++;
    RangeMinimumQuery();
    for(; M; M --)
    {
          scanf("%i %i", &X, &Y);
          printf("%i\n", LCA(X, Y));
    }
    return 0;
}