private static ArrayList<String> PermutationFinder(String nani) {
		String s = nani.toUpperCase(Locale.ENGLISH);
		ArrayList<String> perm = new ArrayList<String>();
		if (s == null) { // error case
			return null;
		} else if (s.length() > 15) {
			perm.add("try 15 or less alphabets");
			return perm;
		} else if (s.length() == 0) {
			perm.add(""); // initial
			return perm;
		}

		char initial = s.charAt(0); // first character
		String rem = s.substring(1); // Full string without first character
		ArrayList<String> words = PermutationFinder(rem);
		for (String str : words) {
			for (int i = 0; i <= str.length(); i++) {
				perm.add(charinsert(str, initial, i));
			}
		}
		return perm;
	}