Queue using array

Program of queue using array
# include<stdio.h>
# define MAX 5
int queue_arr[MAX];
int rear = -1;
int front = -1;
main()
{
int choice;
while(1) {
printf("1.Insert\n");
printf("2.Delete\n");
printf("3.Display\n");
printf("4.Quit\n");
printf("Enter your choice : ");
scanf("%d",&choice);
switch(choice) {
case 1 :
insert();
break;
case 2 :
del();
break;
case 3:
display();
break;
case 4:
exit(1);
default:
printf("Wrong choice\n");
}/*End of switch*/
}/*End of while*/
}/*End of main()
*/
insert()
{
int added_item;
if (rear==MAX-1) printf("Queue Overflow\n");
else
{
if (front==-1)  /*If queue is initially empty */
front=0;
printf("Input the element for adding in queue : ");
scanf("%d", &added_item);
rear=rear+1;
queue_arr[rear] = added_item ;
}
}/*End of insert()*/
del(){
if (front == -1 || front > rear)
{
printf("Queue Underflow\n");
return ;
}
else
{
printf("Element deleted from queue is : %d\n", queue_arr[front]);
front=front+1;
}
}/*End of del() */
display()
{
int i;
if (front == -1)
printf("Queue is empty\n");
else
{
printf("Queue is :\n");
for(i=front;i<= rear;i++)
printf("%d  ",queue_arr[i]);
printf("\n");
}}/*End of display() */