Partition: Tracing

Exercise Trace the first pass of running quicksort (applying partitioning process) on the following sequence. Take the right-most element as pivot.

$$ 20, \space 13, \space 7, \space 71, \space 31, \space 10, \space 5, \space 50, \space 17 $$

Solution
2013771311055017
5137713110205017
5137103171205017
5137101771205031

Items in bold indicate the elements which were swapped.