题目描述:
Write a function that takes an unsigned integer and returns the number of ’1‘ bits it has (also known as the Hamming weight).
For example, the 32-bit integer ’11‘ has binary representation 00000000000000000000000000001011, so the function should return 3.
解题思路:
注意是无符号整形。
1 class Solution { 2 public: 3 int hammingWeight(uint32_t n) { 4 int count = 0; 5 while (true) { 6 if (n == 0) break; 7 if (n == 1) { 8 ++count; 9 break; 10 } 11 12 if (n & 1 != 0) { 13 ++count; 14 } 15 n >>= 1; 16 } 17 18 return count; 19 } 20 };
原文：http://www.cnblogs.com/skycore/p/5338992.html