What are the disadvantages of using an array to implement Queue?

1.	What are the disadvantages of using an array to implement Queue?
Answer» The cons of using an array to implement a queue are: Even if the queue is empty, if it has a significant number of ENQUEUE and dequeue OPERATIONS, we may not be able to INSERT entries at some time (as in the case of linear increment of front and rear indices) (this PROBLEM is solved by using circular queue). When using an array to construct a queue, there may be occasions where we need to extend the queue to insert additional elements. Because it is nearly impossible to extend the array size when using an array to implement a queue, determining the suitable array size is ALWAYS an issue.

Answer»

The cons of using an array to implement a queue are:

Even if the queue is empty, if it has a significant number of ENQUEUE and dequeue OPERATIONS, we may not be able to INSERT entries at some time (as in the case of linear increment of front and rear indices) (this PROBLEM is solved by using circular queue).
When using an array to construct a queue, there may be occasions where we need to extend the queue to insert additional elements. Because it is nearly impossible to extend the array size when using an array to implement a queue, determining the suitable array size is ALWAYS an issue.

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