Circular Queue Implementation Using Array

PROGRAM:

#include<stdio.h>
#include<conio.h>
#define SIZE 5
int count=0,front=-1,rear=-1,cq[SIZE];
void enqueue();
void dequeue();
void display();
void main()
{
 int ch;
 clrscr();
 printf("$$$ CIRCULAR QUEUE USING ARRAY $$$");
 while(1)
 {
  printf("\nCircular Queue operations are:");
  printf("\n1.enqueue\n2.dequeue\n3.display\n4.exit\n");
  printf("Enter your choice:");
  scanf("%d",&ch);
  switch(ch)
  {
   case 1:enqueue();break;
   case 2:dequeue();break;
   case 3:display();break;
   case 4:exit(0);
   default:printf("Enter correct option");
    break;
  }
 }
}
void enqueue()
{
 int item;
 if(count==SIZE)
 {
  printf("Circular Queue is full");
 }
 else
 {
  printf("Enter the element to be inserted:");
  scanf("%d",&item);
  if(front==-1)
  {
   front=0;
  }
  rear=(rear+1)%SIZE;
  cq[rear]=item;
  count=count+1;
 }
}
void dequeue()
{
 if(count==0)
 {
  printf("Circular Queue is empty");
 }
 else
 {
  printf("The deleted element is %d",cq[front]);
  front=(front+1)%SIZE;
  count=count-1;
 }
}
void display()
{
 int i,j;
 if(count==0)
 {
  printf("Circular Queue is empty");
 }
 else
 {
  printf("Elements of circular queue:\n");
  j=front;
  for(i=0;i<count;i++)
  {
   printf("%d\n",cq[j]);
   j=(j+1)%SIZE;
  }
 }
}


OUTPUT:

$$$ CIRCULAR QUEUE USING ARRAY $$$
Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:11

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:22

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:33

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:44

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:55

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Circular Queue is full

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:3
Elements of circular queue:11 22 33 44 55

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:2
The deleted element is 11

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:1
Enter the element to be inserted:66

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:3
Elements of circular queue:22 33 44 55 66

Circular Queue operations are:
1.enqueue
2.dequeue
3.display
4.exit
Enter your choice:4