[Leetcode 191] Number of 1 Bits

Source: Internet
Author: User

1 topics

Write a function that takes an unsigned integer and returns the number of ' 1 ' bits it has (also known as the Hamming weigh T).

For example, the 32-bit integer ' One ' 00000000000000000000000000001011 has a binary representation, so the function should return 3.

Special thanks to @ts for adding this problem and creating all test cases.

2 analysis

Start thinking is to convert to bit array again a check whether it is 1, later found the Java system function Bitcount, found to meet the conditions.

Another way I look at others is by looping 32 times, each time with 1 and moving one bit to the right. The idea is fine.

3 Code

 public  int  hammingweight (int   N) { return   Integer.bitcount (n); }
       Public int hammingweight (int  n) {            int sum=0;              for (int i=0;i<32;i++) {                sum+=n&1;               n= n>>1;            }             return sum;        }

[Leetcode 191] Number of 1 Bits

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.