Insertion in Queue of type Linked list by R4R Team

program-

#include< stdio.h>
#include< conio.h>
#include< alloc.h>
struct node
{
int data;
struct node *next;
};
struct node *front=NULL,*rear=NULL;
void create()
{
struct node *ptr,*cpt;
char ch;
printf("Enter item\n");
ptr=(struct node*)malloc(sizeof(struct node));
scanf("%d",&ptr->data);
front=ptr;
do
{
cpt=(struct node*)malloc(sizeof(struct node));
printf("Enter item\n");
scanf("%d",&cpt->data);
ptr->next=cpt;
ptr=cpt;
printf("Continue(y/n)?");
ch=getch();
}while(ch=='y');
ptr->next=NULL;
rear=ptr;
}
void display()
{
struct node *ptr;
ptr=front;
printf("Queue is : \n");
while(ptr!=NULL)
{
printf("%d ",ptr->data);
ptr=ptr->next;
}
}

void insertion()
{
struct node *ptr;
ptr=(struct node*)malloc(sizeof(struct node));
printf("Enter item to insert\n");
scanf("%d",&ptr->data);
rear->next=ptr;
ptr->next=NULL;
rear=ptr;
}

void main()
{
clrscr();
create();
display();
insertion();
display();
getch();
}

output-

Enter item
9
Enter item
5
Continue(y/n)?
Enter item
1
Continue(y/n)?
Enter item
6
Continue(y/n)?
Enter item
8
Continue(y/n)?
Queue is :
9 5 1 6 8
Enter item to insert
2
Queue is :
9 5 1 6 8 2

-In this program, we have three function create() and traverse(),insertion().
- create() : is used to create a queue using linked list.
- display() : is used to traverse the queue from front to rear.
- insertion() : is used to insert the item in the queue at rear side.