标签:amp represent return problem wiki repr pre ret ble
题目:
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.
链接: http://leetcode.com/problems/number-of-1-bits/
2/22/2017, Java
1 public class Solution { 2 // you need to treat n as an unsigned value 3 public int hammingWeight(int n) { 4 int count = 0; 5 for (int i = 0; i < 32; i++) { 6 count += ((n >> i) & 1); 7 } 8 return count; 9 } 10 }
还有Brian Kernighan的方法,每次去除最低位的1,运算的次数就是count。留给二刷
标签:amp represent return problem wiki repr pre ret ble
原文地址:http://www.cnblogs.com/panini/p/6431531.html