Chapter 5.4, Problem 52E

quick sort is an efficient algorithm. To sort $a_{\text{1}},a_{\text{2}},\dots ,a_n$this algorithm begins by taking the first element $a_{\text{1}}$and forming tow sublists, the first containing those elements that are less than $a_{\text{1}}$, in the order they arise, and the second containing those elements greater than $a_{\text{1}}$, in the order they arise. Then $a_{\text{1}}$is put at the end of the first sub list. This procedure is repeated recursively for each sublists, until all sublists contain one item. The ordered list ofnitems is obtained by combining the sublists of one item in the order they occur.

52. Describe the quick sort algorithm using pseudocode.