The document describes quick sorting an array of numbers from 17 to 3 in multiple steps. It starts with the original array of 17, 10, 15, 13, 4, 12, 7, 9, 16, 8, 5, 14, 3. The first step picks the middle element, 12, as the pivot and rearranges the array so that all elements less than 12 are to its left and all elements greater than or equal to 12 are to its right.
