from random import shuffle y = [1]*5 + [0]*3 shuffle(y) def rec(A): if len(A) <= 1: return A left = rec(A[:len(A)//2]) right = rec(A[len(A)//2:]) print(left+right) if len(A) == 2: if A[0] == A[1]: return [A[0]] else: return [] rec(y)