/**
 * This IntegerSet is a representation of a set of unordered
 * distinct integers. An array will be used to represent 
 * this set.
 * @author USER
 *
 */
public class IntegerSet {
	/**
	 * The array that representing a set.  This element, once
	 * initialized, holds the set property at all time.  
	 */
	int[] element;

	/**
	 * Create a new IntegerSet from a set provided.  The
	 * new set will have the same elements as the set provided.
	 * @param set
	 */
	public IntegerSet(IntegerSet set) {
		// create an array with the same size
		this.element = new int[set.element.length];
		
		// copy all elements
		for (int i = 0; i < this.element.length; i++)
			this.element[i] = set.element[i];
	}
	
	/**
	 * Create an integer set from the array provided.
	 * If the array has many element with the same value,
	 * initialize the set's element with only the distinct
	 * array's elements.
	 * @param array original array
	 */
	public IntegerSet(int[] array) {
		// check that array exists
		if (array == null) return;
		if (array.length < 2) {
			element = array;
			return;
		}
		java.util.Arrays.sort(array);
		// copy all elements
		int[] tmp = new int[array.length];
		tmp[0] = array[0];
		int i = 1, j = 1;
		while (i < array.length) {
			// only copy if an adjacant element different
			if (array[i] != array[i-1]) {
				tmp[j] = array[i];
				j++;
			}
			i++;
		}
		element = java.util.Arrays.copyOf(tmp, j);
	}
	
	/**
	 * This method will check that the array provided is 
	 * considered a set or not.  An array is considered a set 
	 * if all of its elements are distinct.
	 * @para data an array of integer to test for a set property 
	 * @return true if this array is a set, and false otherwise.
	 */
	public static boolean isASet(int[] data) {
		return false;
	}
	
	/**
	 * This method will check that the number is a member
	 * of this set or not.
	 * @param number an integer to check
	 * @return true if the number is a member of this set, 
	 * and false otherwise.
	 */
	public boolean isMember(int number) {
		return false;
	}
	
	/**
	 * Check that this set is empty or not
	 * @return true if this set is empty, and false otherwise
	 */
	public boolean isEmpty() {
		return false;
	}
	
	/**
	 * Check whether this IntegerSet is a subset of the set provided.
	 * Set A is a subset of B if all elements in A are in B.
	 * @param set the set provided.
	 * @return true if this IntegerSet is a subset of the set
	 * 		   provided, and false otherwise.
	 */
	public boolean isSubsetOf(IntegerSet set) {
		return false;
	}
	
	/**
	 * Check whether this IntegerSet is equal to the set provided.
	 * Two set is considered to be equal if they are subset
	 * of each other.
	 * @param set the set provided.
	 * @return true if both set are equal, and false otherwise.
	 */
	public boolean equals(IntegerSet set) {
		return false;
	}

	/**
	 * Union this IntegerSet with the set provided, the result
	 * is a new IntegerSet which all of its elements are member 
	 * of this IntegerSet or the provided set.
	 * @param set the set provided.
	 * @return new IntegerSet that is the result from union
	 */
	public IntegerSet union(IntegerSet set) {
		return null;
	}
	
	/**
	 * Intersect this IntegerSet with the set provided, the result
	 * is a new IntegerSet which all of it elements are member
	 * of this IntegerSet and the provided set.
	 * @param set the set provided
	 * @return new IntegerSet that is the result from intersection
	 */
	public IntegerSet intersect(IntegerSet set) {
		return null;
	}
		
}