Concept of Circular Queue
Circular Queue: A circular queue is a linear data structure that follows the FIFO (First In, First Out) principle but connects the last position back to the first position to form a circle. It overcomes the limitation of a regular queue by efficiently utilizing memory.
Circular queues are widely used in scenarios like CPU scheduling, memory management, and buffering data streams.
How does it work?
- Enqueue operation adds an element to the rear of the queue.
- Dequeue operation removes an element from the front of the queue.
- When the rear reaches the end, it wraps around to the beginning if there is space.
- The queue is full when the next position of the rear is the front.
Important Observations
- Efficiently utilizes memory by reusing empty spaces.
- Requires careful handling of front and rear pointers.
- Can be implemented using arrays or linked lists.
Key Characteristics:
- Fixed size with circular wrapping.
- Efficient for scenarios with repetitive enqueue and dequeue operations.
- Prevents memory wastage compared to a linear queue.
Advantages:
- Efficient memory utilization.
- Prevents overflow in scenarios where elements are dequeued frequently.
- Simple and easy to implement.
Disadvantages:
- Fixed size limits the number of elements.
- Requires additional logic to handle the circular nature.
Time Complexity:
- Enqueue: O(1).
- Dequeue: O(1).
- Peek: O(1).