title: How to assign a character based on the number of times it duplicates in an array
body: <p>I have an array of values that I want to loop through and assign a numerical value starting from 1 on and on. If the same value appears again in the array, I want to append the first value it was assigned with the letter A. If it appears again, I want to append it with the letter B. For example:</p>
  
  <pre><code>myArray=[12,15,6,9,11,14,25,6,13,17,6] 
  </code></pre>
  
  <p>Expected output should be >></p>
  
  <pre><code>1
  2
  3
  4
  5
  6
  7
  3A
  8
  9
  3B
  </code></pre>