singly linked list in python

1class Node:
2    def __init__(self, data, next1):
3        self.data = data
4        self.next = next1
5
6
7class Linkedlist:
8    def __init__(self):
9        self.head = None
10        self.size = 0
11
12    def length(self):
13        return self.size
14
15    def is_empty(self):
16        return self.size == 0
17
18    def insert_at_the_beginning(self, data):
19        self.insert_with_index(0, data)
20
21    def insert_at_the_ending(self, data):
22        self.insert_with_index(self.size, data)
23
24    def insert_with_index(self, index, data):
25        if index > self.size or index < 0:
26            print("check given", index, "index value and enter again")
27            return False
28        if index == 0:
29            self.head = Node(data, self.head)
30        else:
31            current = self.head
32            for i in range(index - 1):
33                current = current.next
34            current.next = Node(data, current.next)
35        self.size += 1
36
37    def peek_top(self):
38        return self.peek_index(0)
39
40    def peek_bottom(self):
41        return self.peek_index(self.size - 1)
42
43    def peek_index(self, index):
44        if index >= self.size or index < 0:
45            print("check given", index, "index value and enter again")
46            return False
47        current = self.head
48        for i in range(index):
49            current = current.next
50        return current.data
51
52    def peek_element(self, data):
53        current = self.head
54        while current.data != data:
55            if current.next is None:
56                print("element", data, "not found")
57                return False
58            current = current.next
59        print("element", data, "is found")
60        return True
61
62    def delete_top_element(self):
63        return self.delete_with_index(0)
64
65    def delete_bottom_element(self):
66        return self.delete_with_index(self.size - 1)
67
68    def delete_with_index(self, index):
69        if index >= self.size or index < 0:
70            print("check given", index, "index value and enter again")
71            return False
72        self.size -= 1
73        if index == 0:
74            temp = self.head
75            self.head = self.head.next
76            return temp.data
77        current = self.head
78        for i in range(index - 1):
79            current = current.next
80        temp = current.next
81        current.next = current.next.next
82        return temp.data
83
84    def delete_with_value(self, data):
85        current = self.head
86        previous = current
87        while current.data != data:
88            if current.next is None:
89                print("element", data, "not found")
90                return False
91            previous = current
92            current = current.next
93        temp = previous.next
94        previous.next = current.next
95        print("element", data, "is found and deleted")
96        self.size -= 1
97        return temp.data
98
99    def print_val(self):
100        current = self.head
101        while current:
102            print(current.data, "\b--->", end="")
103            current = current.next
104        print()
105
106
107linked_list = Linkedlist()
108
109
110def trail1():
111    linked_list.insert_at_the_beginning(45)
112    linked_list.insert_at_the_beginning(65)
113    linked_list.insert_at_the_beginning(34)
114    linked_list.insert_at_the_beginning(56)
115    linked_list.insert_at_the_beginning(78)
116    linked_list.insert_at_the_beginning(98)
117    linked_list.insert_at_the_beginning(63)
118    linked_list.insert_at_the_beginning(31)
119    linked_list.print_val()
120
121
122def trail2():
123    linked_list.insert_at_the_beginning(78)
124    linked_list.insert_at_the_ending(67778)
125    linked_list.insert_at_the_ending(899)
126    linked_list.insert_at_the_ending(99)
127    linked_list.print_val()
128    trail1()
129
130
131def trail3():
132    linked_list.insert_at_the_beginning(34)
133    linked_list.insert_at_the_beginning(56)
134    linked_list.insert_at_the_beginning(78)
135    linked_list.insert_at_the_beginning(31)
136    linked_list.insert_at_the_ending(12)
137    linked_list.insert_at_the_ending(14)
138    linked_list.insert_at_the_ending(56)
139    linked_list.insert_with_index(90, 345)
140    linked_list.insert_with_index(5, 23)
141    print(linked_list.peek_index(2))
142    print(linked_list.peek_bottom())
143    print(linked_list.peek_top())
144    linked_list.peek_element(16)
145    linked_list.peek_element(33)
146    linked_list.insert_at_the_beginning(128)
147    linked_list.insert_at_the_beginning(784)
148    linked_list.insert_at_the_beginning(314)
149    linked_list.print_val()
150    print(linked_list.delete_with_index(5))
151    linked_list.print_val()
152    print(linked_list.delete_top_element())
153    linked_list.print_val()
154    print(linked_list.delete_bottom_element())
155    linked_list.print_val()
156    linked_list.delete_with_value(12)
157    linked_list.print_val()
158    # trail2()
159
160    # this is siva
161    # signing off
162
163
164if __name__ == "__main__":
165    trail3()
166