// Include
#include <fstream>
#include <vector>
using namespace std;

// Constante
const int sz = (int)1e5+1;
const int lgsz = 21;

// Functii
void dfs(int node);

// Variabile
ifstream in("lca.in");
ofstream out("lca.out");

int nodes, questions;
int limit;

vector<int> graph[sz];
int pos[sz];

int LG[sz<<2];
int RMQ[lgsz][sz<<2];

// Main
int main()
{
	in >> nodes >> questions;
	int node;
	for(int i=2 ; i<=nodes ; ++i)
	{
		in >> node;
		graph[node].push_back(i);
	}
	dfs(1);
	
	for(int i=2 ; i<=limit ; ++i)
		LG[i] = LG[i/2]+1;
	
	for(int i=1 ; (1<<i)<=limit ; ++i)
		for(int j=1 ; j<=limit ; ++j)
			RMQ[i][j] = min(RMQ[i-1][j], RMQ[i-1][j+(1<<i-1)]);
	
	int rFrom, rTo;
	while(questions--)
	{
		in >> rFrom >> rTo;
		
		int left = pos[min(rFrom, rTo)];
		int right = pos[max(rFrom, rTo)];
		
		int line = LG[right - left + 1];
		
		out << min(RMQ[line][left], RMQ[line][right-(1<<line)+1]) << '\n';
	}
	
	in.close();
	out.close();
	return 0;
}

void dfs(int node)
{
	RMQ[0][++limit] = node;
	pos[node] = limit;
	
	vector<int>::iterator it, end;
	for(it=graph[node].begin(), end=graph[node].end() ; it!=end ; ++it)
	{
		dfs(*it);
		RMQ[0][++limit] = node;
	}
}