What is the value of front and rear in queue?

What is the value of front and rear in queue?

There are two variables i.e. front and rear, that are implemented in the case of every queue. Front and rear variables point to the position from where insertions and deletions are performed in a queue. Initially, the value of front and queue is -1 which represents an empty queue.

When queue is implemented using array What does the rear variable contains?

To implement a queue using array, create an array arr of size n and take two variables front and rear both of which will be initialized to 0 which means the queue is currently empty. Element rear is the index upto which the elements are stored in the array and front is the index of the first element of the array.

What are the use of front and rear pointers in circular queue implementation?

Operations on Circular Queue Front: It is used to get the front element from the Queue. Rear: It is used to get the rear element from the Queue. enQueue(value): This function is used to insert the new value in the Queue.

What are the conditions that followed in the array implementation of queue?

In array implementation of queue, we create an array queue of size n with two variables top and end. Now, initially, the array is empty i.e. both top and end are at 0 indexes of the array. And as elements are added to the queue (insertion) the end variable’s value is increased.

What is the value for front for an empty queue?

Empty Queue front= -1, rear= -1.

Which one of the following is the correct way to increment the rear end in a circular queue?

In contrast, the last element is connected to the first element in a circular queue; if initial spaces are vacant, then rear can be incremented by using the statement (rear+1) mod max where max is the size of the array. Therefore, we conclude that the circular queue avoids wastage of memory.

How is an array implemented in a queue?

Array implementation of queue (Simple) In queue, insertion and deletion happen at the opposite ends, so implementation is not as simple as stack . To implement a queue using array, create an array arr of size n and take two variables front and rear both of which will be initialized to 0 which means the queue is currently empty.

How to increment the size of a queue?

Increment rear size by 1. Note, that the increment should not cross array index bounds. Which means if suppose queue capacity is 100 and size is 10 and rear is at 99 which means front will be at 89. Now when you enqueue a new element to queue, rear must get updated to 0 instead of 100.

What are the operations of a circular queue?

Operations on Circular Queue: Front: Get the front item from queue. Rear: Get the last item from queue. enQueue (value) This function is used to insert an element into the circular queue. In a circular queue, the new element is always inserted at Rear position.

How to use queue, enqueue and dequeue in C?

Say data = queue [front]; Increment front by 1. Similar to enqueue, the increment should not cross array index bounds. Which means if suppose queue capacity is 100 and size is 10 and rear is at 9 which means front will be at 99. Now when you dequeue element from queue, front must get updated to 0 instead of 100.