#include<iostream>
#include<fstream>
#include<vector>
std::ifstream in("lca.in");
std::ofstream out("lca.out");
#define PI pair<int, long> 
using namespace std;
const int NMAX = 2e5 + 1;
const int LOG = 20;
const int MOD = 1e9 + 7;
int up[NMAX][LOG + 1];
int n, query;
vector<int>d, v, g[NMAX / 2 + 1];
void dfs(int node) {
	v[node] = 1;
	for (auto i : g[node]) {
		if (!v[i]) {
			d[i] = d[node] + 1;
			up[i][0] = node;
			for (int j = 1; j < LOG; j++)
				up[i][j] = up[up[i][j - 1]][j - 1];
			dfs(i);
		}
	}
}
int lca(int a, int b) {
	if (d[a] < d[b]) swap(a, b);
	int k = d[a] - d[b];
	for (int i = LOG - 1; i >= 0; i--)
		if (k & (1 << i)) a = up[a][i];
	if (a == b) return a;
	for (int i = LOG - 1; i >= 0; i--)
		if (up[a][i] != up[b][i]) {
			a = up[a][i];
			b = up[b][i];
		}
	return up[a][0];
}
int main() {
	in >> n >> query;
	v = d = vector<int>(n + 1);
	for (int i = 2; i <= n; i++) {
		int u;
		in >> u;
		g[u].push_back(i);
		g[i].push_back(u);
	}
	dfs(1);
	for (int i = 1; i <= query; i++) {
		int u, v;
		in >> u >> v;
		out << lca(u, v) << '\n';
	}
	return 0;
}