public int count(String dithered, String[] screen) {
		
		int c = 0;
		
		for (String s : screen) {
			int len = s.length();
			for (int i = 0; i < len; i++) {
				if(dithered.indexOf(s.charAt(i)) != -1){
					c++;
				}
			}
		}
		
		return c;
	}