Write a function that takes an unsigned integer and returns the number of ‘1’ bits it has (also known as the Hamming weight).
Example 1:
Input: 11
Output: 3
Explanation: Integer 11 has binary representation 00000000000000000000000000001011
Example 2:
Input: 128
Output: 1
Explanation: Integer 128 has binary representation 00000000000000000000000010000000
思路：
- 转化为二进制数，直接遍历
- 蛮力法 ~~~ class Solution(object): def hammingWeight(self, n): “”” :type n: int :rtype: int “”” nb = bin(n)[2::1] print(nb) c = (‘0’*(32-len(nb)) + nb) print(c) i = 0 for temp in c: if temp == ‘1’: i += 1 return i
if name == “main”: n = Solution().hammingWeight(128) print(n) ~~~
网上思路： https://blog.csdn.net/coder_orz/article/details/51323188
