title: Check Odd numbers without modulo operator
body: <p>I am creating a function that returns whether the passed in number is odd Without the modulo operator. The tricky part is that it should work for NEGATIVE numbers and ZERO.</p>
  
  <p>here's my codes so far:</p>
  
  <pre><code>function testodd(num) {
    return (num/2)*2==num;
  }
  
  var output = testodd(17);
  console.log(output); // --&gt; true
  </code></pre>
  
  <p>Am I making some mistakes here? Or is there a better way to do this?</p>