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Number of 1 Bits

Detailed guide and Python implementation for the 'Number of 1 Bits' problem.

Problem Statement

Easy

Write a function that takes the binary representation of a positive integer and returns the number of set bits it has (also known as the Hamming weight).

Write a function hammingWeight(n: int) -> int.

Constraints
  • n must be a positive integer up to 2^32 - 1

Examples

Example 1
Input
n = 11
Output
3
Explanation

The binary representation of 11 is 1011, which has 3 set bits.

Example 2
Input
n = 128
Output
1
Explanation

The binary representation of 128 is 10000000, which has 1 set bit.

Need a Hint?
Consider using Bit Manipulation-specific data structures like sets or heaps.
Edge Cases to Watch
  • Empty input structures
  • Single element inputs
  • Large numerical bounds

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