public int countBooks(String[] readParts) {
		int count = 0;
		for (int i = 0; i < readParts.length - 2; i++) {
			if (!readParts[i].equals(readParts[i + 1]) &&
					!readParts[i + 1].equals(readParts[i + 2]) &&
					!readParts[i].equals(readParts[i + 2])) {
				count++;
				i += 2;
			}
		}
		return count;
	}