#include <fstream>

using namespace std;

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

const int Nmax = 100005;

int n, m, t[20][Nmax], r[Nmax], Log2[Nmax];

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

void Solve()
{
    int x, y;
    while(m--)
    {
        f>>x>>y;
        if(r[x] < r[y]) swap(x,y);
        while(r[x] > r[y])
        {
            int k = Log2[r[x] - r[y]];
            x = t[k][x];
        }
        if(x == y)
            g<<x<<'\n';
        else
        {
            for(int k = Log2[r[x]]; k>=0 ; k-- )
            {
                if(t[k][x]!=t[k][y])
                {
                    x = t[k][x];
                    y = t[k][y];
                }
            }

            g<<t[0][x]<<'\n';
        }
    }
}

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