Problem Statement  
We have an array of positive integers. We will transform this array by repeating the following operation until there are less than two elements left:
For example, suppose we have an array of four integers {3, 2, 3, 2}. The transformation process goes like this: Step 1: (3, 2, 3, 2) > (3, 1, 3, 1) (decreasing values 2 and 2) Step 2: (3, 1, 3, 1) > (3, 3) (decreased elements became zeros, so we removed them) Step 3: (3, 3) > (2, 2) Step 4: (2, 2) > (1, 1) Step 5: (1, 1) > () Thus, we have an empty array at the end of the process. You are given a int[] elements which represents the array to transform. Return the number of steps in the transformation process.  
Definition  
 
Constraints  
  elements will contain between 1 and 50 elements, inclusive.  
  Each element of elements will be between 1 and 1000, inclusive.  
Examples  
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