public static string isBalanced(string s)
    {
        bool isBalanced = true;
        int count = 0;
        Console.WriteLine(s);
        Stack myStack = new Stack();
        Dictionary<char,char> myDict = new Dictionary<char,char>();
        myDict.Add(')','(');
        myDict.Add('}','{');
        myDict.Add(']','[');
        for(int i = 0; i < s.Length; i++){
            if(myDict.ContainsKey(s[i]) && count > 0)
            {
                if(Convert.ToChar(myStack.Pop())!=myDict.GetValueOrDefault(s[i]))
                    isBalanced = false;
                count--;
            }
            else
            {
                 myStack.Push(s[i]);
                 count++;
            }
        }
        
        return (isBalanced) ? "YES" : "NO";
    }