#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
using namespace std;
ofstream g("lca.out");
ifstream f("lca.in");
const int NMAX = 1e5;
vector<int> tree[NMAX];
int depth[NMAX], value[NMAX], pos[NMAX];
int index = 0;

int n, m;
void citire() {
	f >> n >> m;
	tree[0].push_back(1);
	for (int i = 2; i <= n; i++) {
		int x;
		f >> x;
		tree[x].push_back(i);
	}
}
void euler(int &i,int parent,int d) {
	value[++i] = parent;
	depth[i] = d;
	pos[parent] = i;
	for (auto e : tree[parent]) {
		euler(i, e,d+1);
		value[++i] = parent;
		depth[i] = d;

	}
}
void lca(int x, int y) {
	int min = 1<<10;
	if (x > y)swap(x, y);
	for (int i = pos[x]; i <= pos[y]; i++) {
		if (value[i] < min) {
			min = value[i];
		}
	}
	g << min << endl;
}
int main()
{
	citire();
	depth[0] = 0;
	euler(index,1,0);
	for (int i = 0; i < m; i++) {
		int x, y;
		f >> x >> y;
		lca(x, y);
	}

}