* Bug in del(list) logic. Say you have a list of 4 elements a[0-3]
and you have to remove index 1 and 3, if you remove index 1 first
then list is cut short a[0-2] and does not have index 3
Fix: Remove indexes in reverse sorted order e.g. 3 and 1 in above
example so that order of indexes remain preserved even after deleting
fix is to remove indexes in reverse sorted order
* Add test cases for failed case
0bbea9a579