//https://infoarena.ro/problema/lca
//#pragma GCC optimize ("Ofast")
//#pragma GCC optimize ("fast-math")
//#pragma GCC optimize ("unroll-loops")
//#define _USE_MATH_DEFINES
#include <iostream>
#include <fstream>
#include <vector>
#include <utility>
//#include <queue>
//#include <algorithm>
//#include <cmath>
//#include <climits>
//#include <bitset>
//#include <iomanip>
using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");

vector <pair <int, int>> v;
vector <pair <int, int>> rez;
vector <vector <int>> gr;
vector <int> b;
void dfs(int vf)
{
	//cout << vf << " " << k << "\n";
	b[vf] = 1;
	rez.emplace_back(vf, v[vf].second);

	for (int x : gr[vf])
	{
		if (!b[x])
		{
			dfs(x);
			rez.emplace_back(vf, v[vf].second);
		}
	}
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n, m, i, j, q, p;

	fin >> n >> m;

	v.resize(n + 1);
	b.resize(n + 1);
	gr.resize(n + 1);
	v[1].first = 0;
	v[1].second = 0;
	

	for (i = 2; i <= n; ++i)
	{
		fin >> v[i].first;
		v[i].second = v[v[i].first].second + 1;

		gr[i].push_back(v[i].first);
		gr[v[i].first].push_back(i);
	}

	/*for (i = 1; i <= n; ++i)
	{
		cout << i << " " << v[i].first << " " << v[i].second << "\n";
	}*/

	dfs(1);

	/*for (auto x : rez)
	{
		cout << x.first << " " << x.second << "\n";
	}*/

	for (i = 1; i <= m; ++i)
	{
		fin >> q >> p;

		int qp = 0, pp = 0, minif = 2000000, minis = 2000000;
		for (j = 0; j < rez.size(); ++j)
		{
			if (rez[j].first == q)
			{
				qp = j;
			}
			if (rez[j].first == p)
			{
				pp = j;
			}
		}
		//cout << qp << " " << pp << "\n";

		for (j = min(qp, pp); j <= max(qp, pp); ++j)
		{
			if (minis > rez[j].second)
			{
				minis = rez[j].second;
				minif = rez[j].first;
			}
		}

		fout << minif << "\n";
	}

	return 0;
}