numberof1bits.js

/*
Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight).

Example 1:
Input: n = 00000000000000000000000000001011
Output: 3
Explanation: The input binary string 00000000000000000000000000001011 has a total of three '1' bits.

Example 2:
Input: n = 00000000000000000000000010000000
Output: 1
Explanation: The input binary string 00000000000000000000000010000000 has a total of one '1' bit.

Example 3:
Input: n = 11111111111111111111111111111101
Output: 31
Explanation: The input binary string 11111111111111111111111111111101 has a total of thirty one '1' bits.
*/

/**
 * @param {number} n - a positive integer
 * @return {number}
 */
 var hammingWeight = function(n) {
    let x = n.toString(2).match(/1/g); // toString(2) convert number to binary
    return x?.length || 0;
};