6 3 2 5 0 200 10

pick 6 as the pivot point, after pivotting

  <= 6     >= 6
/-----\   /----\
3 2 5 0 6 200 10
        ^---------pivot
	
0 1 2 3 4 5   6
        ^---------index of pivot
	
	
6 3 2 5 0 200 10

b = 0
e = 6
i = 0

after the first inner loop,
b = 5
after the second inner loop,
e = 5