String longestCompound(String input) { 
		
		input.replaceAll(",", ""); 
		
		ArrayList <String> list = (ArrayList<String>) Arrays.asList(input.split("\\s+/")); 
		
		MyQueue queuer = new MyQueue(); 
		
		for(String word : list) queuer.offer(word); 
		
		while (!queuer.isEmpty()) {
			
			String start = queuer.poll(); 
			
			for (int i = 1; i < start.length(); i++) {
				
				if (queuer.queueMap.containsKey(i) && queuer.queueMap.containsKey(start.length()-i)) {
				
					if (queuer.wordsForLength.get(i).contains(start.substring(0, i)) && 
							queuer.wordsForLength.get(start.length()-i).contains(start.substring(i, start.length()))) {
						return start; 
					}
				}
			}
		}
		
		return null; 
	}