data_structures.queue.circular_queue

Classes

CircularQueue

Circular FIFO queue with a fixed capacity

Module Contents

class data_structures.queue.circular_queue.CircularQueue(n: int)

Circular FIFO queue with a fixed capacity

__len__() → int

>>> cq = CircularQueue(5)
>>> len(cq)
0
>>> cq.enqueue("A")  
<data_structures.queue.circular_queue.CircularQueue object at ...
>>> len(cq)
1

dequeue()

This function removes an element from the queue using on self.front value as an index and returns it >>> cq = CircularQueue(5) >>> cq.dequeue() Traceback (most recent call last):

…

Exception: UNDERFLOW >>> cq.enqueue(“A”).enqueue(“B”).dequeue() ‘A’ >>> (cq.size, cq.first()) (1, ‘B’) >>> cq.dequeue() ‘B’ >>> cq.dequeue() Traceback (most recent call last):

…

Exception: UNDERFLOW

enqueue(data)

This function inserts an element at the end of the queue using self.rear value as an index. >>> cq = CircularQueue(5) >>> cq.enqueue(“A”) # doctest: +ELLIPSIS <data_structures.queue.circular_queue.CircularQueue object at … >>> (cq.size, cq.first()) (1, ‘A’) >>> cq.enqueue(“B”) # doctest: +ELLIPSIS <data_structures.queue.circular_queue.CircularQueue object at … >>> (cq.size, cq.first()) (2, ‘A’)

first()

Returns the first element of the queue >>> cq = CircularQueue(5) >>> cq.first() False >>> cq.enqueue(“A”).first() ‘A’

is_empty() → bool

Checks whether the queue is empty or not >>> cq = CircularQueue(5) >>> cq.is_empty() True >>> cq.enqueue(“A”).is_empty() False

array

front = 0

n

rear = 0

size = 0