python//栈//20191230

class MyStack(object):
    def __init__(self):
        self.stack_list = []
        self.count = 0

    # 创建一个栈
    def create_stack(self):
        return self.stack_list

    # 栈中添加值
    def push(self, value):
        self.stack_list.insert(0,value)
        self.count += 1

    #返回栈顶元素值
    def peek(self):
        if self.count:
            return self.stack_list[0]

    # 删除栈顶元素
    def pop(self):
        self.stack_list.pop(0)
        self.count -= 1

    # 返回栈是否为空
    def is_empty(self):
        return self.count == 0

    #打印栈内容
    def print_all(self):
        for sl in self.stack_list:
            print(sl)

if __name__ == '__main__':
    ms = MyStack()
    ms.create_stack()
    ms.push(1)
    ms.push(2)
    ms.push(3)
    print('栈元素:')
    ms.print_all()
    print('栈顶元素:',ms.peek())
    ms.pop()
    print('栈顶元素删除后:')
    ms.print_all()
    print('栈是否为空:','是' if ms.is_empty() else '否')
    print('---继续删除元素')
    ms.pop()
    print('---继续删除元素')
    ms.pop()
    print('栈是否为空:','是' if ms.is_empty() else '否')