public void targetStringValid() {
		//make sure our target String doesn't have any character not in our alphabet
		//and it does not have the wild character in it
		if(TARGET_STRING.indexOf(WILD_CHAR) > 0) {
			System.out.println("Target String includes our wild character - no good");
			System.exit(0);
		}

		//replace all the characters in our alphabet with "".  See if there is anything left.
		//if there is, we have characters in our target string that are not in our alphabet
		String replacedString = TARGET_STRING;
		for(int i = 0; i < ALPHABET.length(); i++) {
			replacedString = replacedString.replaceAll(String.valueOf(ALPHABET.charAt(i)), "");
		}

		if(replacedString.length() > 0) {
			System.out.println("Target String includes characters that are not in our alphabet - no good");
			System.exit(0);
		}
	}