title: Subtraction with arrays
body: <p>Very simple question: I need the steps not the result please.</p>
  
  <p>Background: I am taking very large numbers and storing them in an array. Then I either add or subtract the two. As it is an array I have to do it column by column. I have the addition done. But for the life of me cannot figure out/remember what to when subtracting a larger number from a smaller.</p>
  
  <p>What are the steps in solving this question column by column?</p>
  
  <pre><code>   50
   -500
   -----
  </code></pre>
  
  <p>EDIT: They are stored in a int[]. Using arrays because it is the assignment requirement.
  Just need to understand the logic of subtraction column by column.</p>