python-实现链式栈

 7 """
  8 用一个类来实现一个节点
  9 """
 10 class Node(object):
 11     def __init__(self,data):
 12         self.data = data
 13         self.next = None
 14 class linkstack(object):
 15     def __init__(self):
 16         self.top = None
 17     def isEmpty(self):
 18         return self.top == None
 19     def clear(self):
 20         self.top = None
 21     def length(self):
 22         i = 0
 23         tempnode  =self.top
 24         while tempnode is not None:
 25             tempnode = tempnode.next
 26             i += 1
 27         return i
 28     def push(self,item):
 29         node = Node(item)
 30         node.next = self.top
 31         self.top  = node
 32     def pop(self):
 33         self.top = self.top.next
 34     def gettop(self):
 35         return self.top.data
 36     def display(self):
 37         if self.top == None:
 38             print("None")
 39         tempnode = self.top
40         while tempnode is not None:
 41             print(tempnode.data,end = " ")
 42             tempnode = tempnode.next
 43         print()
 44
 45 if __name__ == "__main__":
 46     linkstack1 = linkstack()
 47     linkstack1.push(1)
 48     linkstack1.push(2)
 49     linkstack1.push(3)
 50     linkstack1.push(4)
 51     linkstack1.push(5)
 52     linkstack1.push(6)
 53     linkstack1.display()
 54     print(linkstack1.gettop())
 55     print(linkstack1.length())
 56     linkstack1.pop()
 57     linkstack1.display()
 58     linkstack1.clear()
 59     linkstack1.display()
 60     print(linkstack1.isEmpty()) 

运行结果

6 5 4 3 2 1  
6

6

5 4 3 2 1  
None



True

代码逻辑较为简单所以代码没有注释，如果有什么地方不明白，欢迎留言！