3. (5 marks) Consider the following algorithm. Algorithm C Input: a positive integer n at 1 i-n while i > 0 je n while j > 0 k{- n while k > 0 aa * 2 k+ k-1 jt j-1 i i-1 return a (a) What is returned by this algorithm? (b) Use big-O notation to express the running time of this algorithm. Explain your answer, referring specifically to the number of times that each loop would run