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

// Definitii
#define pb push_back

// 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");

bool visited[sz];

int nodes, questions;
int limit;

int pos[sz];

int rmq[lgsz][sz*4];
int LG[sz*4];

vector<int> graph[sz];

// Main
int main()
{
	in >> nodes >> questions;
	int readVal;
	for(int i=2 ; i<=nodes ; ++i)
	{
		in >> readVal;
		graph[readVal].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 dif = right - left + 1;
		int LOG = LG[dif];
		
		int query = min(rmq[LOG][left], rmq[LOG][right-(1<<LOG)+1]);
		out << query << '\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;
	}
}