title: Minimum number of transformation required to equalize an array
body: <p>Given an array of n positive elements (including 0). We are allowed to perform only one transformation which is to increment each element of the list except one. What are the minimum number of transformation required to equalize this list?</p>
  
  <p>For example, <code>n = 3</code>, and the array being <code>1,2,3</code>. We need 3 such transformation as:</p>
  
  <p><code>2,3,3 --&gt; 3,3,4 --&gt; 4,4,4</code>.</p>
  
  <p>For <code>n = 4</code> and the list being <code>1,3,2,4</code> the minimum number of transformation required is 6</p>
  
  <p>Which is the best approach to solve this?</p>