Solution:-
#include<stdio.h>
#include<conio.h>
#include<process.h>
# define maxsize 5
int queue[maxsize];
int rear=-1;
int front=-1;
void cenque( );
void cdeque( );
void display( );
void main( )
{
int choice;
clrscr( );
do
{
printf("\n 1.ENQUEUW");
printf("\n 2.DEQUEUE");
printf("\n 3.DISPLAY");
printf("\n 4.EXIT");
printf("\n Enter your choice: \t");
scanf("%d",&choice);
switch(choice)
{
case 1:
cenque( );
break;
case 2:
cdeque( );
break;
case 3:
display( );
break;
case 4:
exit(0);
break;
}
}
while(choice!=4);
getch( );
}
void cenque( )
{
int item;
if(front==(rear+1)%maxsize)
printf("\n CIRCULAR QUEUE OVERFLOW");
else
{
printf("\n Enter
item: \t");
scanf("%d",&item);
if(front==-1)
{
rear=0;
front=0;
}
else
rear=(rear+1)%maxsize;
queue[rear]=item;
printf("\n %d is
inserted successfully",queue[rear]);
}
}
void cdeque( )
{
int item;
if(front==-1)
printf("\n CIRCULAR QUEUE UNDERFLOW");
else
{
item=queue[front];
if(rear==front)
{
front=-1;
rear=-1;
}
else
front=(front+1)%maxsize;
printf("\n %d is
deleted successfully",item);
}
}
void display( )
{
int i;
if(rear==-1)
printf("\n NO ITEM");
else
{
if(rear>=front)
{
for(i=front;i<=rear;i++)
printf("%d
\t",queue[i]);
}
else
{
for(i=front;i<maxsize;i++)
printf("%d
\t",queue[i]);
for(i=0;i<=rear;i++)
printf(" %d
\t",queue[i]);
}
}
}
