=================================================================================

A recursive algorithm breaks a problem down into smaller problems, and then calls itself for each of the smaller problems. The disadvantages and advantages of the recursive algorithm are:
         i) Different from iteration algorithm, recursive algorithm requests more memory. Therefore, in many languages, iterative solutions are way faster.
         ii) Recursive algorithm sometimes are more abstract or harder to understand.
         iii) Recursive algorithm in some cases are extremely fast and easy to code.

============================================

Recursive function to count up: code:          
         
Output:         
         

============================================

Comparison between iterative algorithm and recursive algorithm: code:          
         
Output:         
         

============================================

Comparison between iterative algorithm and recursive algorithm for sum: code:          
         
Output:         
         

============================================

Comparison between iterative algorithm and recursive algorithm for sum: code:          
         
Output: