#include <iostream>
#include <fstream>

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

const int Nmax = 100005;
int n, m, TT[20][Nmax], r[Nmax], Log2[Nmax];

void Read()
{
    f>>n>>m;
    for(int i = 2; i <= n; i++)
    {
        f>>TT[0][i];
        r[i] = r[TT[0][i]] + 1;
    }
}

void Precalculate()
{
    for(int i = 2; i <= n; i++) Log2[i] = Log2[i/2] + 1;
    for(int i = 1; (1<<i) <= n; i++)
        for(int j = 1; j <= n; j++)
            TT[i][j] = TT[i-1][TT[i-1][j]];
}

void Solve()
{
    int x,y;
    while(m--)
    {
        f>>x>>y;
        if(r[y] > r[x]) swap(x,y);
        while(r[x] > r[y])
        {
            int k = Log2[r[x] - r[y]];
            x = TT[k][x];
        }
        if(x==y) g<<x<<'\n';
        else
        {
            for(int k = Log2[r[y]]; k >= 0; k--)
            {
                if(TT[k][x]!=TT[k][y])
                {
                    x = TT[k][x];
                    y = TT[k][y];
                }
            }
            g<<TT[0][x]<<'\n';
        }
    }
}

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