//ALEXANDRU MICLEA

//solutie cu dinamica de la stramosi / sparse table
//O(n log n) precalculare, O(1) raspuns

#include <vector>
#include <algorithm>
#include <string>
#include <string.h>
#include <cstring>
#include <queue>
#include <map>
#include <set>
#include <unordered_map>
#include <time.h>
#include <iomanip>
#include <deque>
#include <math.h>
#include <cmath>
#include <assert.h>
#include <stack>
#include <bitset>
#include <random>
#include <chrono>
#include <assert.h>
#include <iostream>

using namespace std;
using ll = long long;

#define fast_cin() 	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0)

//VARIABLES

int dp[25][400005];
int LOG[400005];

vector <int> euler;
int pos[100005];
int h[100005];
vector <int> gr[100005];

//FUNCTIONS

void dfs(int nod) {
	euler.push_back(nod);
	pos[nod] = euler.size() - 1;

	for (auto& x : gr[nod]) {
		h[x] = h[nod] + 1;
		dfs(x);
		euler.push_back(nod);
	}
}

//MAIN
int main() {

	#ifdef INFOARENA
		freopen("lca.in", "r", stdin);
		freopen("lca.out", "w", stdout);
	#endif

	fast_cin();

	int n, m; cin >> n >> m;

	for (int i = 2; i <= n * 2; i++) LOG[i] = LOG[i / 2] + 1;

	for (int i = 2; i <= n; i++) {
		int val; cin >> val;
		gr[val].push_back(i);
	}

	dfs(1);

	for (int i = 0; i < euler.size(); i++) {
		dp[0][i] = euler[i];
	}

	for (int p = 1; p <= LOG[2 * n]; p++) {
		for (int i = 0; i < euler.size(); i++) {
			if (h[dp[p - 1][i]] < h[dp[p - 1][i + (1 << (p - 1))]]) {
				dp[p][i] = dp[p - 1][i];
			}
			else {
				dp[p][i] = dp[p - 1][i + (1 << (p - 1))];
			}
		}
	}

	for (int i = 1; i <= m; i++) {
		int x, y; cin >> x >> y;

		x = pos[x];
		y = pos[y];
		if (x > y) swap(x, y);

		int dif = y - x + 1;
		int dist = LOG[dif];

		if (h[dp[dist][x]] < h[dp[dist][y - (1 << dist) + 1]]) cout << dp[dist][x];
		else cout << dp[dist][y - (1 << dist) + 1];
		cout << '\n';
	}

	return 0;
}