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

// Definitii
#define pb push_back

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

// Functii
void dfs(int node);

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

int nodes, questions;
int limit;

int pos[sz];
int LG[sz<<2];

int RMQ[21][sz<<2];
vector<int> graph[sz];

// Main
int main()
{
	in >> nodes >> questions;
	
	int rNode;
	for(int i=2 ; i<=nodes ; ++i)
	{
		in >> rNode;
		graph[rNode].pb(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-(1<<i)+1 ; ++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 = min(pos[rFrom], pos[rTo]);
		int right = max(pos[rFrom], pos[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=graph[node].end();
	for(it=graph[node].begin() ; it!=end ; ++it)
	{
		dfs(*it);
		RMQ[0][++limit] = node;
	}
}