public HashMap<Character, String> returnValues() {
		HashMap<Character, String> rtn = new HashMap<>();
		preOrder(this, "", rtn);
		printPreOrder(this);
		System.out.println(rtn);
		return rtn;
	}
	/**
	 * Traverses the tree and stores the binary representations of the leaves
	 * @param node The current node (C in CLR)
	 * @param binRep The binary representation of the current node
	 * @param hm The hashmap that holds the binary
	 */
	private void preOrder(HuffmanNode node, String binRep, HashMap<Character, String> hm) {
		if(node.isLeaf()) { //base case
			hm.put(Character.valueOf(node.s.charAt(0)), binRep);
		}
		if(node.getLeft() != null) {
			binRep += "0";
			preOrder(node.getLeft(), binRep, hm);
		}
		if(node.getRight() != null) {
			if(node.getLeft() != null) {
				//try creating a new variable here
				binRep = binRep.substring(0, binRep.length() - 1) + "1";
			}
			else {
				binRep += "1";
			}
			preOrder(node.getRight(), binRep, hm);
		}
	}