program 76: Queue implementation on linked list

The need:
    This program shows how one can implement concept of queue in linked lists. I have already told that linked lists are needed when we practically don't want a bound on size of data being used in program. So unlike array implementation this program will never show "cannot enqueue" message until your computer is out of memory.
The code:
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/*
This is a program showing the queue implimentation on linked list
program writtem by RP Singh
compiled and tested on C-free4.0 standard
*/
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
struct node1
{
    int item;
    struct node1 *next;
};
typedef struct node1 node;        //defining datatype node
void enqueue(node *);
node* dequeue(void);
node *create_node(void);
void fill_node(node *);
void print_node(node *);

node *front=NULL, *rear=NULL;                //global implementation of queue

int main()
{
    int i,j;
    node *current_node;
    printf("Enter 3 items into queue\n");
    for(i=0;i<3;i++)
    {
        current_node=create_node();
        fill_node(current_node);
        enqueue(current_node);
        printf("item %d inserted into queue successfully\n",current_node->item);
    }
    printf("all items successfully entered into queue\n");
    printf("press any key to dequeue and see all values you entered");
    fflush(stdin);
    getchar();
    while(!(rear==NULL&&front==NULL))
    {
        current_node=dequeue();
        print_node(current_node);
    }
    return 0;
}

void enqueue(node *p)                    //definition of enqueue function
{
    if(rear==NULL&&front==NULL)
    {
        rear=p;
        front=p;
    }
    else
    {
        rear->next=p;
        rear=p;
    }
}

node *dequeue(void)                    //definition of dequeue function
{
    node *temp=NULL;
    if(rear==NULL&&front==NULL)        //this is the case when queue is empty
    {
        printf("queue is empty hence can not be dequeued\n");
    }
    else if(rear==front&&front!=NULL)    //this is the case when queue has only one node
    {
        temp=front;
        front=NULL;
        rear=NULL;
    }
    else
    {
        temp=front;
        front=front->next;
    }
    return temp;
}

node *create_node()                    //function to create a blank node
{
    node *temp;
    temp=(node*)malloc(sizeof(node));
    temp->next=NULL;
    return temp;
}

void fill_node(node *p)                    //function to fill a blank node with values taken from user
{
    int i;
    printf("Enter an integer\n");
    scanf("%d",&i);                    //this is the value taken from user
    p->item=i;
}

void print_node(node *p)                    //printing the node data
{
    printf("%d\n",p->item);            //in our case node has only one item
}

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