public static void run()
        {
            //IStack stack = new LinkedStack();
            //stack.push(5);
            //stack.push(3);
            //stack.push(4);

            IStack arrayStack = new ArrayStack();
            arrayStack.push(5);
            arrayStack.push(3);
            arrayStack.push(4);
            arrayStack.push(6);
            arrayStack.push(12);

            Console.WriteLine(arrayStack.top());

            arrayStack.pop();

            Console.WriteLine(arrayStack.top());

            Thread.Sleep(1000);
        }
        public static void run()
        {
            //IStack stack = new LinkedStack();
            //stack.push(5);
            //stack.push(3);
            //stack.push(4);

            IStack arrayStack = new ArrayStack();

            arrayStack.push(5);
            arrayStack.push(3);
            arrayStack.push(4);
            arrayStack.push(6);
            arrayStack.push(12);

            Console.WriteLine(arrayStack.top());

            arrayStack.pop();

            Console.WriteLine(arrayStack.top());

            Thread.Sleep(1000);
        }