#include<fstream>
#include<vector>
#include<queue>
using namespace std;

#define limit 17

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

vector<vector<int>> graph;
vector<vector<int>> parent;
vector<int> level;


void build(int root,int n) {
	int u, v, nr;
	for (nr = 1; nr < limit; nr++) {
		queue<pair<int,int>> qp;
		qp.push({ root,1 });
		while (!qp.empty()) {
			auto p = qp.front();
			level[p.first] = p.second;
			qp.pop();
			for (auto v : graph[p.first]) {
				parent[v][nr] = parent[parent[v][nr - 1]][nr - 1];
				qp.push({ v,p.second + 1 });
			}
		}
	}
}

int find(int u, int v) {
	if (level[u] > level[v]) {
		swap(u, v);
	}
	int nr = level[v] - level[u],i;
	for (i = 0; i < limit; i++) {
		if (nr & (1 << i)) {
			v = parent[v][i];
		}
	}
	if (u == v) {
		return u;
	}
	nr = level[u];
	for (i = limit - 1; i >= 0; i--) {
		if (parent[u][i] != parent[v][i]) {
			u = parent[u][i];
			v = parent[v][i];
		}
	}
	return parent[u][0];
}

int main() {
	int i, j, nr, n, m, u, v;

	cin >> n >> m;
	level.resize(n);
	parent = vector<vector<int>>(n, vector<int>(limit,0));
	graph.resize(n);

	for (v = 1; v < n; v++) {
		cin >> u;
		u--;
		parent[v][0] = u;
		graph[u].push_back(v);
	}
	build(0,n);

	while (m--) {
		cin >> u >> v;
		u--;
		v--;
		cout << find(u, v) + 1 << "\n";
	}
	/*for (i = 0; i < n; i++) {
		cout << i + 1 << " : ";
		cout << level[i]<<" | ";
		for (auto nr : parent[i]) {
			cout << nr+1 << " ";
		}
		cout << "\n";
	
	}*/

	return 0;
}