import java.util.*; 

/**
 * The Union-Find algorithm. You must implement this.
 */
public class UnionFind<V> {


	/**
	 * Creates a completely disjoint set over n classes.
	 *
	 * @param n
	 *            The number of classes in the disjoint forest
	 * @throws IllegalArgumentException
	 *             If n is not positive.
	 */
	public UnionFind (int n, Set<V> vertices)
	{

	}

	/**
	 * Finds the cannonical element for this node.
	 *
	 * @param node
	 *            Returns the cannonical class of this node
	 * @throws IllegalArgumentException
	 *             If node is outside of the range [0, num_nodes-1]
	 */
	public int find (V node)
	{
		return -1;
	}

	/**
	 * Merge the two cannonical classes can_one and can_two.
	 *
	 * @param a
	 *            The first cannonical class to merge. Note that these are
	 *            cannonical classes and not just nodes.
	 * @param b
	 *            The second cannonical class to merge.
	 * @throws IllegalArgumentException
	 *             If either a or ais not a valid node or is not the cannonical
	 *             element of its set. In other words, calls to this will
	 *             commonly look like union(find(one), find(two)).
	 */
	public void union (int a, int b)
	{
		
	}
}