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import java.util.HashSet;

/*
 * Example of add(E e) method.
 */
public class HashSetExample
{
    public static void main( String[] args )
    {
        HashSet<String> hashSet = new HashSet<String>();
        
        System.out.println("hashSet: " + hashSet + "\n");

        /*
         * Adds the specified element to this set if it is not already present.
         * 
         * If this set already contains the element, the call leaves the set
         * unchanged and returns false.
         */

        boolean isAdded = hashSet.add("Dave");

        System.out.println("isAdded : " + isAdded);
        System.out.println("hashSet: " + hashSet + "\n");   
        
        isAdded = hashSet.add("Dave");

        System.out.println("isAdded : " + isAdded);
        System.out.println("hashSet: " + hashSet);  

    }
}