#include      <iostream>
#include      <fstream>
#include      <algorithm>
#include      <vector>
#include      <stack>

#define MAX 100005
 
using namespace std;

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

vector < int > G[MAX];

int n, m, H[MAX], L[MAX], p, first[MAX];
bool viz[MAX];
int Rmq[25][MAX << 2], Lg[MAX << 1];

void dfs(int nod, int nivel) {
	H[++p] = nod;
	L[p] = nivel;
	first[nod] = p;

	for (unsigned int i = 0; i < G[nod].size(); i++)
		if (!viz[G[nod][i]]) {
			dfs(G[nod][i], nivel + 1);
			H[++p] = nod;
			L[p] = nivel;
		}
	
}


void rmq(){
	for (int i = 2; i <= p; ++i)
		Lg[i] = Lg[i >> 1] + 1;
	for (int i = 1; i <= p; ++i)
		Rmq[0][i] = i;
	for (int i = 1; (1 << i) < p; ++i)
		for (int j = 1; j <= p - (1 << i); ++j){
			int l = 1 << (i - 1);
			Rmq[i][j] = Rmq[i - 1][j];
			if (L[Rmq[i - 1][j + l]] < L[Rmq[i][j]])
				Rmq[i][j] = Rmq[i - 1][j + l];
		}
}


int lca(int x, int y){
	int diff, l, sol, sh;
	int a = first[x], b = first[y];
	if (a > b) swap(a, b);
	diff = b - a + 1;
	l = Lg[diff];
	sol = Rmq[l][a];
	sh = diff - (1 << l);
	if (L[sol] > L[Rmq[l][a + sh]])
		sol = Rmq[l][a + sh];
	return H[sol];
}

int main() {
	ios::sync_with_stdio(false);
	in.tie(NULL), out.tie(NULL);

	in >> n >> m;
	for (int i = 2; i <= n; i++) {
		int x;
		in >> x;
		G[x].push_back(i);
	}

	dfs(1, 0);
    rmq();
	while (m--) {
		int x, y;
		in >> x >> y;
		out << lca(x, y) << '\n';
	}

	return 0;
}