1. insertion sort
-----------------
initial array:
 7	39	20	11	16	5

39 doesn't need to be inserted:
 7   	39	20	11	16	5

20 is inserted:
 7   	20	39	11	16	5

11 is inserted:
 7   	11	20	39	16	5

16 is inserted:
 7   	11	16	20	39	5

5 is inserted:
 5   	7	11	16	20	39



The following tasks will be moved to next week's lab:


2. initial partitioning by quicksort
------------------------------------
initial array:
 7	39	20	11	16	5

pivot = 20

move i left to right until we find 39
move j right to left until we find 5
swap:
 7	5 	20	11	16	39

continuing left to right, find 20
continuing right to left, find 16
swap:
 7	5 	16	11	20	39

continuing left to right, find 20 in its new location
continuing right to left, find 11
i and j have now crossed, so we don't swap. 

Instead, we return the final value of j (which is 3),
which gives the end of the left subarray.
The two subarrays are:

 7	5 	16	11   |	20	39


3. completing the trace of quicksort
------------------------------------
see the separate image file