liked_list python

linked_list.py

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None


class LinkedList:
    def __init__(self):
        self.tail = None
        self.head = None
        self.cur = None
        self.pre = None

    def append(self, data):
        new_node = Node(data)
        if self.head is None:
            self.head = new_node
            self.tail = new_node
        else:
            self.tail.next = new_node
            self.tail = new_node
            self.tail.next = None

    def pop(self):
        self.pre = self.head

        if self.head == self.tail:
            self.head = None
            return self.tail.data

        while self.pre.next is not self.tail:
            self.pre = self.pre.next
        data = self.tail.data
        self.tail = self.pre
        self.tail.next = None
        return data

    def insert(self, find, data):
        self.cur = self.head
        while True:
            if self.cur == None:
                return
            if self.cur.data == find:
                break
            self.cur = self.cur.next
        temp = self.cur.next
        self.cur.next = Node(data)
        self.cur.next.next = temp


linked_list = LinkedList()
linked_list.append("test")
linked_list.append("test2")
linked_list.append("test3")
linked_list.insert("test2", "test4")
print(linked_list.pop())
print(linked_list.pop())
print(linked_list.pop())
print(linked_list.pop())