#include <fstream>
#include <vector>
#define nmax 100001
#define mmax 2000001
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
int n;
vector <int> v[nmax];
vector < pair <int,int > > q[nmax];
int sol[mmax],t[nmax],anc[nmax],rang[nmax],use[nmax];

int rad(int x)
{
    while(x!=t[x])
        x=t[x];
    return x;
}

void unite(int a, int b)
{
    if(rang[a]==rang[b])
    {
        rang[a]++;
        t[b]=a;
    }
    else if(rang[a]>rang[b]) t[b]=a;
            else t[a]=b;
}
void tarjan(int nod)
{
    t[nod]=nod;
    anc[nod]=nod;
    int i;
    for(i=0;i<v[nod].size();i++)
    {
        tarjan(v[nod][i]);
        unite(rad(nod),rad(v[nod][i]));
        anc[rad(nod)]=nod;
    }
    use[nod]=1;
    for(i=0;i<q[nod].size();i++)
        if(use[q[nod][i].first])
            sol[q[nod][i].second]=anc[rad(q[nod][i].first)];

}
int main()
{
    int i,j,m,x,y;
    f>>n>>m;
    for(i=2;i<=n;i++)
    {
        f>>x;
        v[x].push_back(i);
    }

    for(i=1;i<=m;i++)
    {
        f>>x>>y;
        q[x].push_back(make_pair(y,i));
        q[y].push_back(make_pair(x,i));
    }

    tarjan(1);

    for(i=1;i<=m;i++)
        g<<sol[i]<<'\n';
}