#include <fstream>
#include <vector>
 
using namespace std;
 
#define MAX_N 100005
#define MAX_L 20
 
#define foreach(V) for(typeof (V).begin() it = (V).begin(); it != (V).end(); ++it)
  
int N, M, T[MAX_L][MAX_N], Lg_binary[MAX_N], Lev[MAX_N];
vector <int> G_binary[MAX_N];
 

void dfs_binary(int nod, int lev)
{
	Lev[nod] = lev;
 
	foreach(G_binary[nod])
		dfs_binary(*it, lev+1);
}
 
int lca_binary(int x, int y)
{
	if(Lev[x] < Lev[y])
		swap(x, y);
 
	int log1, log2;
	for(log1 = 1; (1 << log1) < Lev[x]; ++log1);
	for(log2 = 1; (1 << log2) < Lev[y]; ++log2);
 
	for(int k = log1; k >= 0; --k)
		if(Lev[x] - (1 << k) >= Lev[y])
			x = T[k][x];
 
	if(x == y) return x;
 
	for(int k = log2; k >= 0; --k)
		if(T[k][x] && T[k][x] != T[k][y])
			x = T[k][x],
			y = T[k][y];
		
	return T[0][x];
}
 
int Binary(char* inputfile,char* outputfile)
{	clock_t tic = clock();
	ifstream fin;
    ofstream fout;
    fin.open(inputfile);
    fout.open(outputfile);
	fin >> N >> M;
 
	for(int i = 2; i <= N; ++i)
	{
		fin >> T[0][i];
		G_binary[T[0][i]].push_back(i);
	}
 
	int k;
	for(k = 1; (1 << k) <= N; ++k)
		for(int i = 1; i <= N; ++i)
			T[k][i] = T[k-1][T[k-1][i]];

	dfs_binary(1, 0);
 
	while(M--)
	{
		int x, y;
		fin >> x >> y;
		fout << lca_binary(x, y) << "\n";
	}
	clock_t toc = clock();

    printf(" Binary elapsed: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
	return M;
}