LeetCode:Number of 1 Bits

Number of 1 Bits

    My Submissions

Question Editorial Solution

Total Accepted: 90511  Total Submissions: 240977  Difficulty: Easy

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.

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

Subscribe to see which companies asked this question

Hide Tags

  Bit Manipulation

Hide Similar Problems

  (E) Reverse Bits (E) Power of Two (M) Counting Bits

c++ code:

class Solution {
public:
    int hammingWeight(uint32_t n) {
        int count=0;
        while(n)
        {
            if(n & 1) count++;
            n >>= 1;
        }
        return count;
    }
};

java code:

public class Solution {
    // you need to treat n as an unsigned value
    public int hammingWeight(int n) {
        int cnt = 0;
        while(n!=0) {
            cnt++;
            n &= n-1;
        }
        return cnt;
    }
}