forked from kitelife/Data-Structures-and-Algorithms
-
Notifications
You must be signed in to change notification settings - Fork 0
/
arrayqueue.py
37 lines (28 loc) · 842 Bytes
/
arrayqueue.py
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
#!/usr/bin/env python
#Implementation of the Queue ADT using a circular array
from myArray import Array
class Queue:
def __init__(self, maxSize):
self._count = 0
self._front = 0
self._back = maxSize - 1
self._qArray = Array(maxSize)
def isEmpty(self):
return self._count == 0
def isFull(self):
return self._count == len(self._qArray)
def __len__(self):
return self._count
def enqueue(self, item):
assert not self.isFull(), "Cannot enqueue to a full queue."
maxSize = len(self._qArray)
self._back = (self._back + 1) % maxSize
self._qArray[self._back] = item
self._count += 1
def dequeue(self):
assert not self.isEmpty(), "Cannot dequeue from an empty queue."
item = self._qArray[self._front]
maxSize = len(self._qArray)
self._front = (self._front + 1) % maxSize
self._count -= 1
return item