stack.py

"""
@version: python3.6
@author: Fieldhunter
@contact: 1677532160yuan@gmail.com
@time: 2020-05-03
"""
import functools


"""
    Check if the code used to access the stack information,Decorator function.
    The purpose of simply adding code is to prevent stack from 
      being tampered with maliciously and to provide the API for developers.
"""
def check_code(func):
    @functools.wraps(func)
    def check(self, code):
        if code != 'adsf;{h3096j34ka`fd>&/edgb^45:6':
            raise Exception('code is wrong!')
        result = func(self, code)
        return result

    return check


class Sequence_stack():
    def __init__(self):
        self.__data_list = []
        self.__num = 0

    def add_data(self, element):
        self.__data_list.append(element)
        self.__num += 1

    def pop_data(self):
        if self.__data_list != []:
            last_data = self.__data_list[-1]
            del self.__data_list[-1]
            self.__num -= 1

            return last_data
        else:
            print("No data in stack")
            return None

    @check_code
    def return_basic_information(self, code):
        return self.__data_list, self.__num


# linked stack
class link_Node():
    def __init__(self, num):
        self.data = num
        self.next = None


class Linked_stack():
    def __init__(self):
        self.__head = None
        self.__num = 0
    
    def add_data(self, element):
        new_data = link_Node(element)
        new_data.next = self.__head
        self.__head = new_data
        self.__num += 1

    def pop_data(self):
        if self.__head != None:
            last_data = self.__head.data
            self.__head = self.__head.next
            self.__num -= 1

            return last_data
        else:
            print("No data in stack")
            return None

    @check_code
    def return_basic_information(self, code):
        return self.__head, self.__num