Write a class for a set of integers - there are no duplicates in the Set 
A number can be in there only once

class intSet
{ final int MAX = 20;
  private int [] ar = new int[20];
  private int ct;

  public intSet(); // creates empty set
  public void clear();  clears set
  public void add(int n);  //adds n if it is not in set already
  public boolean contains(int n); // returns true if n is in set
  public int size();  // returns number of elements in the set
  public int itemAt(int x);  // returns item in spot x
  public void print();  // prints set of integers
  public void remove(int n); // removes n from set if it is in there
  public boolean equals(intSet is);  //returns true if sets are equal
  public boolean subset(intSet is); //returns true if is is suset of this set
  public intSet union(intSet is); // returns union of 2 sets - all elements 
  public intSet interesection(intSet is); // returns intersection of 2 sets - what they have in common 
 }


Write a driver program that works with at least 2 Integer Sets. 
Make sure you test Union, Intersections and subset.