#include <fstream>
#include <vector>

using namespace std;

#define MAX_N 100005
#define foreach(V) for(typeof (V).begin() it = (V).begin(); it != (V).end(); ++it)

ifstream fin ("lca.in");
ofstream fout ("lca.out");

const int h = 200;

int N, M, T[MAX_N], T2[MAX_N], Lev[MAX_N];
vector <int> G[MAX_N];

void citire()
{
	fin >> N >> M;

	for(int i = 2; i <= N; ++i)
	{
		fin >> T[i];
		G[T[i]].push_back(i);
	}
}

void dfs(int nod, int n1, int lev)
{
	Lev[nod] = lev;
	T2[nod] = n1;

	if(lev % h == 0) n1 = nod;

	foreach(G[nod])
		dfs(*it, n1, lev+1);
}

int lca(int x, int y)
{
	while(T2[x] != T2[y])
		if(Lev[x] > Lev[y])
			x = T2[x];
		else
			y = T2[y];

	while(x != y)
		if(Lev[x] > Lev[y])
			x = T[x];
		else
			y = T[y];

	return x;
}

int main()
{
	citire();
	dfs(1, 0, 0);

	while(M--)
	{
		int x, y;
		fin >> x >> y;

		fout << lca(x, y) << "\n";
	}
}