public int numOfDups(String[] words) {
		if (words.length == 0) {
			return 0;
		}
		Hashtable<String, Integer> hash = new Hashtable<String, Integer>();
		int counter = 0;
		for (int i = 0; i < words.length; i++) {
			if (!hash.containsKey(words[i])) {
				hash.put(words[i], 1);
			} else {
				int c = hash.get(words[i]);
				c++;
				hash.put(words[i], c);
			}
		}

		for (int j = 0; j < words.length; j++) {
			for (int k = 0; k < words.length; k++) {
				if (j != k) {
					String s = words[j] + words[k];
					if (!hash.containsKey(s)) {
						hash.put(s, 1);
					} else {
						int c = hash.get(s);
						c++;
						hash.put(s, c);
					}
				}
			}
		}

		for (String s : hash.keySet()) {
			int c = hash.get(s);
			if (c >= 2) {
				System.out.println("s " +s);
				counter++;
			}
		}
		return counter;

	}