private boolean areParenthesesBalanced(String string) {
		int count = 0;
		for (int i = 0; i < string.length(); i++) {
			if (string.charAt(i) == '(')
				count++;
			else if (string.charAt(i) == ')')
				count--;
			if (count < 0)
				return false;
		}
		return count == 0;
	}