title: Python for loop decrementing index
body: <p>So I wrote a for loop like this:</p>
  
  <pre><code>for i in range(size):
    if(.....)
      ....
      i-=1
    else:
      ....
  </code></pre>
  
  <p>I try to decrease the index by 1 if it is inside the <code>if</code> statement, but apparently I can't do that. Is there any other way that I can decrease <code>i</code> in a for loop?</p>