#include <fstream>

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

const int Nmax = 100005;

int n, m, t[Nmax], r[Nmax];

void Read()
{
    f>>n>>m;
    for(int i = 2; i <= n; i++)
    {
        f>>t[i];
        r[i] = r[t[i]] + 1;
    }
}

void Solve()
{
    int x, y;
    while(m--)
    {
        f>>x>>y;
        if(x < y) swap(x,y);
        while(r[x] > r[y]) x = t[x];
        if(x == y) g<<x<<'\n';
        else
        {
            while(x != y)
            {
                x = t[x];
                y = t[y];
            }
            g<<x<<'\n';
        }
    }
}

int main()
{
    Read();
    Solve();
    return 0;
}