public static String isBalanced(String s) {
        
        Stack<Character> stack = new Stack<>();
        HashMap<Character, Character> map = new HashMap<>();
        map.put(')', '(');
        map.put(']', '[');
        map.put('}', '{');
        
        // \ ({}) \     \ )({}) \
        for (char c : s.toCharArray()) {
            if (map.containsKey(c)) {
                if (!stack.isEmpty() && stack.peek() == map.get(c)) {
                    stack.pop();
                } else {
                    return "NO";
                }
            } else {
                stack.push(c);
            }
        }
        
        return (stack.isEmpty()) ? "YES" : "NO";
    }