p2.c

#include<stdio.h>
#define  SIZE 5
char queue [SIZE];
int front=-1,rear=-1;
void insert()
{
    char ch;
    if((rear+1)%SIZE==front)
    {
        printf("queue is full\n");
        
    }
    else
    {
        printf("enter the character to insert\n");
        scanf("%c",&ch);
        if(front==-1&&rear==-1)
        {
            front=rear=0;
        }
        else
        {
            rear=(rear+1)%SIZE;
        }
        queue[rear]=ch;
        printf("%c inserted\n",ch);
    }
}
void delete()
{
    if(front==-1&&rear==-1)
    {
        printf("empty\n");
    }
    else
    {
        char ch=queue[front];
        if(front==rear)
        {
            front=rear=-1;
        }
        else
        {
            front=(front+1)%SIZE;
        }
        printf("deleted %c\n");
    }
}
void display()
{
    if(front==-1&&rear==-1)
    {
        printf("empty\n");
    }
    else
    {
        printf("elements\n");
        int i=front;
        while(1)
        {
            printf("%c",queue[i]);
            if(i==rear)
            break;
            i=(i+1)%SIZE;
        }
        printf("\nfront=%d,rear=%d",front,rear);
        
    }
}
int main()
{
   int choice;
   while(1)
   {
       printf("insert\n");
       printf("delete\n");
       printf("display\n");
       printf("exit\n");
       printf("enter the choice\n");
       scanf("%d",&choice);
       switch(choice)
       {
           case 1:insert();
           break;
           case 2:delete();
           break;
           case 3:display();
           break;
           case 4:printf("exiting program");
           return 0;
           default:printf("invalid choice\n");
           
       }
   }
}