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！