FilesExpand file tree

 master

/

linked_queue.py

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

58 lines (45 loc) · 1.21 KB

 master

/

linked_queue.py

Copy path

Top

File metadata and controls

• Code
• Blame

58 lines (45 loc) · 1.21 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

"""

Queue based upon linked list

Author: Wenru

"""

from typing import Optional

class Node:

def __init__(self, data: str, next=None):

self.data = data

self._next = next

class LinkedQueue:

def __init__(self):

self._head: Optional[Node] = None

self._tail: Optional[Node] = None

def enqueue(self, value: str):

new_node = Node(value)

if self._tail:

self._tail._next = new_node

else:

self._head = new_node

self._tail = new_node

def dequeue(self) -> Optional[str]:

if self._head:

value = self._head.data

self._head = self._head._next

if not self._head:

self._tail = None

return value

def __repr__(self) -> str:

values = []

current = self._head

while current:

values.append(current.data)

current = current._next

return "->".join(value for value in values)

if __name__ == "__main__":

q = LinkedQueue()

for i in range(10):

q.enqueue(str(i))

print(q)

for _ in range(3):

q.dequeue()

print(q)

q.enqueue("7")

q.enqueue("8")

print(q)