CS 07 Project 7:  set operations 1

What is a set?

*A collection of items of the same type. Stored in the some container and no duplicates allowed
The ordering of the objects within the container is of no importance
*equals method must be defined on the elements of the set to be able to compare  new elements 
brought into the set to avoid duplication


ALL OF THESE OPERATIONS CREATE A THIRD SET BUT DO NOT MODIFY THE FIRST TWO SETS (BINARY OPERATIONS)

ASSUME: set1 = { A,B,C,D }  set2 = { C,D,E,F }

UNION set1 + set2 = { A,B,C,D,E,F } // all elements combined minus duplicates

INTERSECTION  set1 * set2 = { C,D } // only the elements in common between them

DIFFERENCE set1 - set2 = set1 with the intersection elements removed
set1 - set2 = { A,B }

XOR (exclusive or) written as set1 xor set2
set1 xor set2  = union(of the two sets) - intersection(of the two sets)
	      = { A,B,C,D,E,F } - { C,D } = { A,B,E,F }

equals method must be defined to be able to test new strings brought into the set to avoid duplication