#include <iostream>
#include<fstream>
#include<cmath>
#include<vector>
#define Nmax 100001
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n, m, k, nivel[2 * Nmax], h[2 * Nmax], lg[2 * Nmax], prap[Nmax];
vector<int>fiu[Nmax];
int rmq[20][4 * Nmax];
void dfs(int nod, int niv)
{
    h[++k] = nod;
    nivel[k] = niv;
    prap[nod] = k;
    vector<int>::iterator it;
    for(it = fiu[nod].begin(); it != fiu[nod].end(); it++)
    {
        dfs(*it, niv + 1);
        h[++k] = nod;
        nivel[k] = niv;
    }
}
void rangemq() //rmq[i][j]- nodul de nivel min dintre poz j,j+2^i-1 din reprez euler
{
    for(int i = 2; i <= k; i++)
        lg[i] = lg[i >> 1] + 1;
    for(int i = 1; i <= k; i++)
        rmq[0][i] = i;
    for(int i = 1; (1 << i) < k; i++)
        for(int j = 1; j < k - (1 << i); j++)
        {
            int l = 1 << (i - 1);
            rmq[i][j] = rmq[i - 1][j];
            if(nivel[rmq[i - 1][j + l]] < nivel[rmq[i][j]])
                rmq[i][j] = rmq[i - 1][j + l];
        }
}
int lca(int x, int y)
{
    int a = prap[x], b = prap[y];
    if(a > b)
        swap(a, b);
    int diferenta = b - a + 1;
    int l = lg[diferenta];
    int  sol = rmq[l][a];
    int sh = diferenta - (1 << l);
    if(nivel[sol] > nivel[rmq[l][a + sh]])
        sol = nivel[rmq[l][a + sh]];
    return h[sol];
}
int main()
{
    int x, y;
    f >> n >> m;
    for(int i = 2; i <= n; i++)
    {
        f >> x;
        fiu[x].push_back(i);
    }
    dfs(1, 0);
    rangemq();
    for(int i = 1; i <= m; i++)
    {
        f >> x >> y;
        g << lca(x, y) << '\n';
    }
    return 0;
}