Parenthesis Checker

        s:
            string input;
            int a = 0;
            int Tcount = 0;

            Stack ch = new Stack();
            Console.WriteLine("Input Anything :");
            input = Console.ReadLine();

            foreach (char c in input)
            {
                if (c.Equals('('))
                {
                    ch.Push('(');
                    Tcount += 1;

                }
                else if (c.Equals(')'))
                {
                    try
                    {
                        ch.Pop();
                        a++;
                    }
                    catch(Exception)
                    {
                        Console.WriteLine("( is expected");
                        Console.ReadLine();
                        goto s;
                    }
                }
            }


            if (ch.Count == 0)
            {
                Console.WriteLine(Tcount + " valid ");

            }
            else
            {
                Console.WriteLine( ") is expected");
            }
            goto s;