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Bit ManipulationDynamic Programming
Given a non-negative integer n, write a function to return the number of '1' bits in its binary representation (also known as the Hamming weight).
For example, given the integer n = 11, which is 1011 in binary, the number of '1' bits is 3.
Example 1
Input
[ 11 ]
Output
3
Explanation. The binary representation of 11 is 1011, which has three '1' bits.
Example 2
Input
[ 128 ]
Output
1
Explanation. The binary representation of 128 is 10000000, which has one '1' bit.
Example 3
Input
[ 255 ]
Output
8
Explanation. The binary representation of 255 is 11111111, which has eight '1' bits.
Example 4
Input
[ 0 ]
Output
0
Explanation. The binary representation of 0 is 0, which has no '1' bits.
Follow-up: Can you implement this in linear time complexity without using any built-in bit manipulation functions?
Constraints:
The input must be a non-negative integer.
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