89. Number of 1 Bits

Easy · Bit Manipulation

Write a function that takes a positive integer and returns the number of 1-bits present in its binary representation.

For example, the number 5 has binary representation 101, which contains two 1-bits. The number 9 has binary representation 1001, which also contains two 1-bits.

Examples

Example 1
Input: 5
Output: 2
Explanation: 5 in binary is 101, which has two 1-bits.
Example 2
Input: 9
Output: 2
Explanation: 9 in binary is 1001, which has two 1-bits.

Constraints