new_contents: """
  The Hamming distance between two integers is the number of positions at which the corresponding bits are different.
  
  Given two integers x and y, calculate the Hamming distance.
  
  Note:
      0 ≤ x, y < 2 ** 31.
  
  Example:
  
      Input: x = 1, y = 4
      
      Output: 2
  
  Explanation:
      1   (0 0 0 1)
      4   (0 1 0 0)
             ↑   ↑
  
  The above arrows point to positions where the corresponding bits are different.
  """
  class Solution(object):
      def hammingDistance(self, x, y):
          """
          :type x: int
          :type y: int
          :rtype: int
          """
          # Solution using reduce
          #from functools import reduce # If python3.x
          #return int(reduce(lambda i, j: int(i) + int(j), bin(x^y)[2:]))
          return bin(x^y)[2:].count('1')
  
  a = Solution()
  print(a.hammingDistance(1, 4) == 2)
  
subject: add 461