<pre class="shiki github-dark shaku"><code>function countOne(num) { return num.toString(2).replace(/0/g, '').length;}</code></pre>

One line solution

Given an integer, count "1" in its binary form. countOne(1) // 1, "1"countOne(257799) // 12, "111110111100000111" 1. If you use built-in string method…