title: Making equal size lists in Python
body: <p>I have 3 different lists of unequal length.</p>
  
  <p>I want to append the shorter lists with "X" and make sizes equal to the length of the longest list.</p>
  
  <pre><code>A = [10,20,30,40,50]
  B = ["A", "B", "C"]
  C = ["X1", "X2"]
  </code></pre>
  
  <p>After appending "X" , it should be like the following:</p>
  
  <pre><code>A = [10,20,30,40,50]
  B = ["A", "B", "C", "X","X"]
  C = ["P1", "P2", "X", "X", "X"]
  </code></pre>
  
  <p>I have used the below code for achieving it,</p>
  
  <pre><code>for i, a in enumerate(A):
      if i &lt; len(B):
          pass
      else:
          B.append('X')
  </code></pre>
  
  <p>How can i do it efficiently in python ?</p>