#include <fstream>
#include <vector>
#define N 100005
#define L 20
#define foreach(V) for (typeof (V).begin() it = (V).begin(); it != (V).end(); ++it)

using namespace std;

int k, n, m;
int l[N << 1], h[N << 1], lg[N << 1], ap[N];
int Rmq[L][N << 2];
vector <int>  v[N];

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

void citire()
{
	
	
	f>>n>>m;
	for (int i = 2; i <= n; ++i)
	{
		int x;
		f>>x;
		v[x].push_back(i);
	}
}

void eul(int nod, int nivel)
{
	
	h[++k] = nod;
	l[k] = nivel;
	ap[nod] = k;

	foreach(v[nod])
	{
		eul(*it, nivel + 1);
		
		h[++k] = nod;
		l[k] = nivel;
	}
}

void rmq()
{
	for (int i = 2; i <= k; ++i){
		lg[i] = lg[i >> 1] + 1;
	}

	for (int i = 1; i <= k; ++i){
		Rmq[0][i] = i;
	}

	for(int i = 1; (1 << i) < k; ++i){
		for (int j = 1; j <= k - (1 << i); ++j){
			int ll = 1 << (i - 1);

			Rmq[i][j] = Rmq[i - 1][j];
			if(l[Rmq[i - 1][j + ll]] < l[Rmq[i][j]]){
				Rmq[i][j] = Rmq[i -1][j + ll];
			}
		}
	}
}

int lca(int x, int y)
{
	int diff, ll, sol, sh;
	int a = ap[x];
	int b = ap[y];
	if(a > b) swap(a, b);
	diff = b - a + 1;
	ll = lg[diff];
	sol = Rmq[ll][a];
	sh = diff - (1 << ll);
	if (l[sol] > l[Rmq[ll][a + sh]])
		sol = Rmq[ll][a + sh];
	return h[sol];

}
int main()
{
	citire();
	eul(1, 0);
	rmq();
	while(m--){
		int x, y;
		f>>x>>y;
		g<<lca(x, y)<<"\n";

	}

	return 0;
}