title: Multiply by 0.5 rather than divide by 2
body: <p>While I was reading tips in C, I have seen this tip here <a href="http://www.cprogramming.com/tips/tip/multiply-rather-than-divide" rel="noreferrer">http://www.cprogramming.com/tips/tip/multiply-rather-than-divide</a>
  but I am not sure. I was told both multiply and divide are slower and time consuming and requires many cycles.</p>
  
  <p>and I have seen people often use <code>i &lt;&lt; 2</code> instead of <code>i x 4</code> since shifting is faster.</p>
  
  <p>Is it a good tip using <code>x0.5 or /2</code> ? or however modern compilers do optimize it in a better way?</p>