Problem: Starting with array S[] = (123, 34, 189, 56, 150, 12, 9, 240) indexed from 1 to 8:
a) Assuming that Quick Sort uses the first item in the list as the pivot item, sort S using Quick Sort. Show the recursive tree. Show the recursive tree and indicate order of execution, i.e., label steps in tree nodes.
b) Give a list of 8 items that represent the worst case scenario. Describe the reason why it represents a worst case as well as its time complexity with n inputs.