Stuff

def separar(r):
	aux=''
	lista=[]
	print r
	while (len(r)>4):
		for i in range (len(r)-1,len(r)-5,-1):
			z=r.pop(i)
			aux=aux+z
		        print aux
		lista.append(aux)
		aux=''
	aux=r[0]
	lista.append(aux)
	return lista

def convert_binario(n):
	r = []
      	aux=''
      	while n:
        	r.append(str(n & 1))
              	n >>= 1
      	return r

def folding(ok):
	aux=ok[0]
	aux=int(aux)
	for count in range(1, len(ok)-1):
		aux=aux^int(ok[count])
	print aux

r=convert_binario(5000)
ok=separar(r)
folding(ok)