1. class node:
2.     def __init__(self, pdata):
3.         self.data = pdata
4.         self.pointer = None
5.  
6. class linkedlist:
7.     def __init__(self):
8.         self.head = None
9.  
10.     def insertfront(self, pdata):
11.         newnode = node(pdata)
12.         if self.head is None:
13.             self.head = newnode
14.             return
15.         else:
16.             newnode.pointer = self.head
17.             self.head = newnode
18.  
19.     def insertindex(self, data, index):
20.         newnode = node(data)
21.         currentnode = self.head
22.         pos = 0
23.         if pos == index:
24.             self.insertfront(data)
25.         else:
26.             while (currentnode != None and pos+1 != index):
27.                 pos+=1
28.                 currentnode = currentnode.pointer
29.  
30.         if currentnode != None:
31.             newnode.pointer = currentnode.pointer
32.             currentnode.pointer = newnode
33.         else:
34.             print("index not present")
35.  
36.     def insertEnd(self, data):
37.         newnode = node(data)
38.         if self.head is None:
39.             self.insertfront(data)
40.             return
41.         else:
42.             currentnode = self.head
43.             while (currentnode.pointer):
44.                 currentnode = currentnode.pointer
45.  
46.             currentnode.pointer = newnode
47.  
48.  
49.     def Output(self):
50.         currentnode = self.head
51.         while (currentnode.pointer != None):
52.             print(currentnode.data)
53.             currentnode = currentnode.pointer
54.  
55.         print(currentnode.data)
56.  
57.     def Delfront(self):
58.         if self.head == None:
59.             return
60.         else:
61.             self.head = self.head.pointer
62.  
63.     def Dellast(self):
64.         if self.head == None:
65.             return
66.         elif self.head.pointer == None:
67.             self.Delfront()
68.         else:
69.             currentnode = self.head
70.             while currentnode.pointer.pointer != None:
71.                 currentnode = currentnode.pointer
72.  
73.             currentnode.pointer = None
74.  
75.     #def deleteatend(self):
76.  
77. print("af, means add to front of linked listn"
78.       "al, means add to last of linked listn"
79.       "ai, means add to index of linked listn"
80.       "df, means delete from front of linked listn"
81.       "dl, means delete from last of linked listn"
82.       "di, means delete from index of linked listn"
83.       "o, means output linked listn")
84. x = ""
85. llist = linkedlist()
86. while x != "e":
87.     x = input("What do you want to do to the linked listn>>>")
88.     if x == "af":
89.         y = input("Enter the data")
90.         llist.insertfront(y)
91.     elif x == "al":
92.         y = input("Enter the data")
93.         llist.insertEnd(y)
94.     elif x == "ai":
95.         y = input("Enter the data")
96.         index = int(input("Enter the index location"))
97.         llist.insertindex(y, index - 1)
98.     elif x == "df":
99.         llist.Delfront()
100.     elif x == "dl":
101.         llist.Dellast()
102.     elif x == "o":
103.         print("Llist is starting>")
104.         llist.Output()
105.         print("<Thats all folks")
106.     else:
107.         print("please input something appropriate")