#include <bits/stdc++.h>
#define Nmax 100001
#define Mmax 400004
using namespace std;

int rmq[22][Mmax];
int E[Mmax], k, n;
int niv[Mmax], poz[Nmax];
int P[Mmax];
vector <int>L[Nmax];

void Euler(int nod, int nivel)
{
    E[++k] = nod;
    niv[k] = nivel;
    poz[nod] = k;

    for (auto i : L[nod])
    {
        Euler(i, nivel + 1);
        E[++k] = nod;
        niv[k] = nivel;
    }
}

void RMQ()
{
    int i, j, x, y;
    /// P -> RMQ
    P[1] = 0;
    for (i = 2; i <= k; i++)
        P[i] = 1 + P[i / 2];

    /// RMQ         FORM
    for (i = 1; i <= k; i++)
        rmq[0][i] = i;

    int lg = P[k]; /// k -> nr de valori depuse in Euler[] (E[])
    for (i = 1; i <= lg; i++)
        for (j = 1; j <= k - (1 << i) + 1; j++)
        {
            x = niv[rmq[i - 1][j]];
            y = niv[rmq[i - 1][j + (1 << (i - 1))]];
            if (x < y) rmq[i][j] = rmq[i - 1][j];
            else rmq[i][j] = rmq[i - 1][j + (1 << (i - 1))];
        }
}

int main()
{
    /// Citire
    int i, j, Q;
    int x, y;
    ifstream fin("lca.in");
    fin >> n >> Q;
    for (i = 2; i <= n; i++)
    {
        fin >> x;
        L[x].push_back(i);
    }

    Euler(1, 1);
    RMQ();

    /// interogarile
    ofstream fout("lca.out");
    while (Q--)
    {
        fin >> x >> y;
        x = poz[x];
        y = poz[y];
        if (x > y) swap(x, y);

        int lg = P[y - x + 1];
        i = rmq[lg][x];
        j = rmq[lg][y - (1 << lg) + 1];
        if(niv[i] < niv[j])
            fout << E[i] << "\n";
        else fout << E[j] << "\n";
    }
    fout.close();
    return 0;
}