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

#define NMAX 100002

using namespace std;

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

int n, q, k, dad[NMAX], rmq[20][NMAX], log2[NMAX], depth[NMAX], poz[NMAX];
vector<int> G[NMAX];

void citire()
{
    fin >> n >> q;
    for (int i = 2; i <= n; i++)
    {
        fin >> dad[i];
        G[dad[i]].push_back(i);
    }

    dad[1] = 1;
}

void dfs(int nod)
{
    poz[nod] = k;
    rmq[0][k++] = nod;
    depth[nod] = depth[dad[nod]] + 1;

    for (auto it : G[nod])
    {
        dfs(it);
        rmq[0][k++] = nod;
    }
}

int main()
{
    citire();

    dfs(1); // path eulerian

    /// construim rmq
    for (int i = 1; (1<<i) < k; i++)
    {
        for (int j = 0; j+(1<<i) < k; j++)
        {
            if (depth[rmq[i-1][j]] < depth[rmq[i-1][j+(1<<(i-1))]])
                rmq[i][j] = rmq[i-1][j];
            else
                rmq[i][j] = rmq[i-1][j+(1<<(i-1))];
        }
    }

    /// queries
    log2[1] = 0;
    for (int i = 2; i <= n; i++)
        log2[i] = log2[(i>>1)] + 1;

    for (int i = 1; i <= q; i++)
    {
        int x, y;
        fin >> x >> y;

        x = poz[x]; y = poz[y];
        if (x > y) swap(x, y);

        int level = log2[y - x + 1];
        if (depth[rmq[level][x]] < depth[rmq[level][y-(1<<level)+1]])
            fout << rmq[level][x] << "\n";
        else
            fout << rmq[level][y-(1<<level)+1] << "\n";
    }
    return 0;
}