#include <fstream>
#include <vector>
using namespace std;
ifstream cin ("lca.in");
ofstream cout ("lca.out");
int viz[100010],tata[100010],p,p_start[100010],p_end[1000108];
vector <int> lista[100010];
void dfs(int nod)
{
    int i;
    viz[nod]=1;
    p++;
    p_start[nod]=p;
    for (i=0; i<lista[nod].size(); i++)
        if (viz[lista[nod][i]]==0)
            dfs(lista[nod][i]);
    p++;
    p_end[nod]=p;
}
int stramos(int x,int y)
{
    if (p_start[x]<=p_start[y] && p_end[y]<=p_end[x])
        return 1;
    return 0;
}
int main()
{
    int n,q,i,x,y,pp;
    cin>>n>>q;
    for (i=2; i<=n; i++)
    {
        cin>>tata[i];
        lista[i].push_back(tata[i]);
        lista[tata[i]].push_back(i);
    }
    p=0;
    dfs(1);
    for (i=1; i<=q; i++)
    {
        cin>>x>>y;
        pp=0;
        while (pp==0)
        {
            if (stramos(x,y)==1)
            {
                cout<<x<<"\n";
                pp=1;
            }
            else
                if (stramos(y,x)==1)
                {
                    cout<<y<<"\n";
                    pp=1;
                }
                else
                {
                    x=tata[x];
                    y=tata[y];
                }
        }
    }
    return 0;
}