12, 18, 17, 11, 13, 15, 16, 14. 15 is pivot swap it with right most element
12, 18, 17, 11, 13, 14, 16, | 15
12, 11, 17, 18, 13, 14, 16, | 15
12, 11, 13, 18, 17, 14, 16, | 15
12, 11, 13, 14, 17, 18, 16, | 15
12, 11, 13, 14, 15, 18, 16, | 17
12, 11, 13, 14, 15, 18, 16, 17
clearly 12 and 16 are not changed.
if we use pivot as leftmost element then 16 doesn't change
12, 18, 17, 11, 13, 15, 16, 14. 15 is pivot swap it with left most element
15 | 18, 17, 11, 13, 12, 16, 14
15 | 11, 17, 18, 13, 12, 16, 14
15 | 11, 13, 18, 17, 12, 16, 14
15 | 11, 13, 12, 17, 18, 16, 14
15 | 11, 13, 12, 14, 18, 16, 17
14 | 11, 13, 12, 15, 18, 16, 17
in this case answer is seven