1. A set is like a bag, except that a set does not allow multiple copies of any element. If you try to insert a new copy of an item that is already present in a set, then the set simply remains...

1. A set is like a bag, except that a set does not allow multiple copies of any element. If you try to insert a new copy of an item that is already present in a set, then the set simply remains unchanged. For this project, implement a set as a new class that is extended from one of your bags.