python实现栈,队列

栈(LIFO)

class Stack(object):
    """
    使用 python 实现栈
    栈是一种LIFO(Last In First Out) 的数据结构,可以封装一个list实现
    """

    def __init__(self):
        self.__stack = list()

    def push(self, value):
        """
        append 到列表尾部,复杂度 O(1)
        :param value:
        :return:
        """
        self.__stack.append(value)

    def pop(self):
        """
        pop 弹出
        :return:
        """
        return self.__stack.pop()

    def isEmpty(self):
        """

        :return:
        """
        return len(self.__stack) == 0

    def size(self):
        """

        :return:
        """
        return len(self.__stack)


if __name__ == "__main__":
    stack = Stack()
    stack.push(0)
    stack.push(1)
    stack.push(2)
    stack.push(3)
    print(stack.size())
    print(stack.pop())

队列(FIFO)

class Queue(object):

    def __init__(self):
        self.__queue = list()

    def push(self, value):
        self.__queue.append(value)

    def pop(self):
        return self.__queue.pop(0)

    def isEmpty(self):
        return len(self.__queue) == 0

    def size(self):
        return len(self.__queue)


if __name__ == "__main__":
    q = Queue()
    q.push(0)
    q.push(1)
    q.push(2)
    print(q.pop())
    print(q.pop())
    print(q.pop())