Advantages of Circular Queue over Linear Queue

Last Updated on April 20, 2023 by Prepbytes

The circular queue has several advantages over linear queue. It uses memory more efficiently because it can reuse the space that becomes available when elements are dequeued. The circular queue can be used for both FIFO and LIFO structures, while the linear queue only supports FIFO structure.

What is Linear Queue?

A linear queue is a data structure that works on the principle of first-in, first-out (FIFO) and has a linear structure, meaning that its elements are arranged in sequential order. It has two pointers, one pointing to the front of the queue and another pointing to the rear. When an element is added, it is inserted at the rear end, and when an element is removed, it is removed from the front end. The size of the linear queue is fixed and elements are stored in contiguous memory locations. Insertion of elements from the rear end in the queue is known as enqueue operation and deletion of elements from the front end of the queue is known as dequeue operation. In this queue, the rear end always lies after the front end of the queue.

Circular Queue

A circular queue is a data structure that behaves like a queue but wraps around itself, forming a circle instead of a straight line. It has a fixed size and consists of a front and rear pointer. When an element is added, it is inserted at the rear and when an element is removed, it is removed from the front. If the rear pointer reaches the end of the queue, it wraps around to the beginning, allowing for efficient use of memory. In this type of queue, the element can be added in any position or can be deleted from any position in the array but we have to maintain the pointers which will point towards the front and rear end of the queue. In this queue, the rear end can be at any point in the array.

Example of Circular Queue over Linear Queue

Here, are the example of circular queue over linear queue:

1. When Enqueue operation is performed on both types of queues:
   Let the queue is of size 6 having elements {5, 10, 15, 20, 25, 30}. In both the queues the front points at the first element 5 and the rear points at the last element 30 as shown in the below image:

2. When the dequeue operation is performed on both the queues:
   When the dequeue operation is performed on both queues the first 2 elements are deleted from both queues. In both the queues the front points at the element with value 15 and the rear points at the element with value 30 as shown in the below image:

   

3. Now again enqueue operation is performed:
   When enqueue operation is performed an element with a value of 35 is inserted in both the queues. The insertion of element 35 is not possible in Linear Queue but in the Circular Queue, the element with a value of 35 is possible as shown in the below image:

   

Explanation:

• The insertion in the queue is done from the rear end and in case of Linear Queue of fixed size insertion is not possible when rear reaches the end of the queue.
• But in the Circular Queue, the rear end moves from the last position to the front position circularly.

Advantages of Circular Queue

Here, are the advantages of circular queue:

• There is an efficient use of memory.
• It can be used for both FIFO and LIFO structures.
• The circular queue has better performance than a linear queue for certain use cases.
• It is easy to implement and understand.
• It supports circular buffering for streaming data applications.

Advantages of Circular Queue Over Linear Queue

Here are the advantages of circular queue over linear queue:

• Efficient use of memory: In a circular queue, when the rear pointer reaches the end of the queue, it wraps around to the beginning, which allows for efficient use of memory compared to a linear queue.
• Easier for insertion-deletion: In the circular queue, if the queue is not fully occupied, then the elements can be inserted easily in the vacant locations. But in the case of a linear queue, insertion is not possible once the rear pointer reaches the last index even if there are empty locations present in the queue.
• Better performance: Circular queue offers better performance in situations where data is frequently added and removed from the queue as compared to a linear queue.
• Simplified implementation: Implementing a circular queue is simpler as compared to a linear queue as it requires less complexity and fewer conditional statements.
• Improved flexibility: With a circular queue, the front and rear pointers can move in either direction, allowing for greater flexibility in implementing queue operations.
• Reduced overhead: Since a circular queue requires a fixed amount of memory, it reduces the overhead of memory allocation and deallocation as compared to a dynamic data structure like a linked list-based linear queue.

Disadvantages of Circular Queue

Here, are some disadvantages of circular queue:

• It has limited capacity, which can lead to overflow and data loss.
• These are more complex to implement than a simple linear queue.
• It can be difficult to debug when there are errors.
• They require additional logic to handle empty and full states.
• It can be slower than a linear queue for certain use cases.

Conclusion
In conclusion, the advantages of circular queue over linear queue is a useful data structure that provides efficient memory usage, supports both FIFO and LIFO structures, and can be used for streaming data applications. However, it also has some limitations such as limited capacity, the complexity of implementation, and potential performance issues in certain use cases. So, the choice of using a circular queue or a linear queue depends on the specific requirements of the application.

Frequently Asked Questions(FAQs)

Q1. What are the advantages of using a queue data structure?
Ans: Queues are useful in situations where data needs to be processed in a specific order. They offer efficient insertion and deletion of elements and can be used to implement scheduling algorithms, buffer systems, and other similar applications.

Q2. What are the advantages of circular queue over linear queue?
Ans: The advantages of circular queue over linear queue.Circular queue has several advantages over the linear queue, such as better memory usage efficiency, support for both FIFO and LIFO structures, and better performance for streaming data applications.

Q3. When should I use a circular queue instead of a linear queue?
Ans: Circular queue is more suitable for use cases where memory efficiency and streaming data applications are important factors. Linear queue, on the other hand, is better for applications that require simple FIFO operations and have a fixed data size.

Q4. What are some disadvantages of using a circular queue?
Ans: Circular queue has some limitations, such as limited capacity, potential complexity in implementation, and potential performance issues in certain use cases.

Q5. How do I implement a circular queue in my code?
Ans: You can implement a circular queue in Java, C++, Python, or any other programming language using an array or a linked list. The implementation details may vary depending on the language and the specific requirements of your application.