#include <fstream>
#include <cstdio>
#include <iostream>
#include <vector>

#define MAXN 100001
#define MAXRMQ 20

#define min(a, b) (a) < (b) ? a : b
#define max(a, b) (a) > (b) ? a : b

using namespace std;

vector<int> tree[MAXN];
int first_appearance_index[MAXN];
int euler_level[MAXN << 2];
int euler_node[MAXN << 2];
int rmq[MAXRMQ][MAXN << 2];
int log[MAXN << 2];
int euler_size;

void calculate_euler(int node, int level) {

	first_appearance_index[node] = euler_size++;
	euler_level[euler_size - 1] = level;
	euler_node[euler_size - 1] = node;

	for(vector<int>::iterator it = tree[node].begin(); it != tree[node].end(); it++) {
		calculate_euler(*it, level + 1);
		euler_size++;
		euler_level[euler_size - 1] = level;
		euler_node[euler_size - 1] = node;
	}
}

void precalculate_rmq() {
	for(int i = 2; i < euler_size; i++)
		log[i] = log[i >> 1] + 1;

	for(int j = 0; j < euler_size; j++)
		rmq[0][j] = j;
	
	int offset;
	for(int i = 1; (1 << i) <= euler_size; i++)
		for(int j = 0; j <= euler_size - (1 << i); j++) {
			offset = 1 << (i - 1);
			rmq[i][j] = rmq[i - 1][j + offset];
			if (euler_level[rmq[i - 1][j]] < euler_level[rmq[i][j]])
				rmq[i][j] = rmq[i - 1][j];
		}
}

int get_rmq_min(int index1, int index2) {
	int distance = index2 - index1 + 1;
	int lg = log[distance];
	int offset = distance - (1 << lg);

	return euler_level[rmq[lg][index1]] < euler_level[rmq[lg][index1 + offset]] ? rmq[lg][index1] : rmq[lg][index1 + offset];
	
}

int main(void) {
	ifstream f("lca.in");
	freopen("lca.out", "w", stdout);
	
	int nodes, queries;
	f >> nodes >> queries;
	
	int father;
	for (int i = 1; i < nodes; i++) {
		f >> father;
		tree[father].push_back(i + 1);
	}

	calculate_euler(1, 0);
	precalculate_rmq();

	int node1, node2;
	int index1, index2;
	while(queries--) {
		f >> node1 >> node2;
		index1 = first_appearance_index[node1];
		index2 = first_appearance_index[node2];
		if (index1 < index2)
			printf("%d\n", euler_node[get_rmq_min(index1, index2)]);
		else
			printf("%d\n", euler_node[get_rmq_min(index2, index1)]);
	}

	return 0;
}