Queue Operations

#include<stdio.h>
#include<malloc.h>
struct node
{
        int data;
        struct node *ptr;
};

struct node * addq(struct node *,int);
void  display(struct node *);
struct node * deleteq(struct node *);
struct node *head,*rear;
int main()
{
        int choice,item;

        rear=NULL;


        for(;;)
        {
                printf("\n Enter the choice : 1-Insert 2- Display");
                printf(" \n 3-Delete 4-Exit : ");
                scanf("%d",&choice);
                switch (choice)
                {

                        case 1 :printf(" \n Enter the number to be added to queue");
                                scanf("%d",&item);
                                rear=addq(rear,item);
                                break;
                        case 2 :display(head);
                                break;
                        case 3 :head=deleteq(head);
                                break;
                        default:exit(0);
                                break;
                }
        }

}

        struct node * addq(struct node *rear,int item)
        {
                struct node *newnode;
                newnode=(struct node *)malloc(sizeof(struct node));
                newnode->data=item;
                newnode->ptr=NULL;

                if(rear==NULL)
                {
                        head=newnode;
                        return newnode;
		 else
                {
                        rear->ptr=newnode;
                        return newnode;
                }
        }

        void display(struct node *head)
        {
                while(head!=NULL)
                {
                        printf("%d \t",head->data);
                        head=head->ptr;
                }
        }

        struct node * deleteq(struct node *head)
        {

                struct node *temp;

                if(head==NULL)
                {
                        printf("\n The queue is empty");
                        return head;
                }

                else
                {
                        temp=head;
                        head=head->ptr;
                        printf(" \n The deleted item is : %d",temp->data);
                        free(temp);
                        return head;
                }
        }