#include <fstream>
#include <vector>
#include <iostream>
#include <cmath>

using namespace std;

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

const int NMax = 1e5;

int TT[NMax + 5], A[20][NMax + 5], Lev[NMax + 5], N, M;

vector <int> G[NMax + 5];

void DFS(int Nod)
{
    Lev[Nod] = Lev[TT[Nod]] + 1;

    for(auto Vecin : G[Nod])
        DFS(Vecin);
}

void Precalc()
{
    for(int i = 1; (1 << i) <= N; i++)
    {
        for(int x = 1; x <= N; x++)
            A[i][x] = A[i - 1][A[i - 1][x]];
    }
}

int Stramos(int Nod, int P)
{
    int k = 0;

    while(P)
    {
        if(P & 1) Nod = A[k][Nod];

        P >>= 1, k++;
    }
    return Nod;
}

int LCA(int x, int y)
{
    if(Lev[x] < Lev[y]) swap(x, y);

    if(Lev[x] != Lev[y])
        x = Stramos(x, Lev[x] - Lev[y]);

    if(x == y) return x;

    for(int i = log2(Lev[x]); i >= 0; i--)
    {
        if(A[i][x] != A[i][y])
            x = A[i][x], y = A[i][y];
    }
    return A[0][x];
}

int main()
{
    fin >> N >> M;

    for(int i = 2; i <= N; i++)
        fin >> TT[i], A[0][i] = TT[i], G[TT[i]].push_back(i);

    Precalc(), DFS(1);

    for(int i = 0, x, y; i < M; i++)
    {
        fin >> x >> y;

        fout << LCA(x, y) << '\n';
    }
    fin.close();
    fout.close();

    return 0;
}