public static void main(String[] args) {
        Stack<String> stack = new Stack<String>(3);
        stack.push("zhu");
        stack.push("zhen");
        stack.push("guang");

        for (String s : stack) {
            System.out.println(s);
        }

        String removeData = stack.pop();
        System.out.println(removeData);

        for (String s : stack) {
            System.out.println(s);
        }
    }