Insertion and deletion over circular queue

Insert and delete operations are performed on circular queue whose size is 10. Queue follows FIFO format while performing insert and delete operation.First the front and rear is initialized to -1.Numbers are inserted from the positions 0 to 9.While deleting the number ,the first inserted number is removed first i.e. the numbers are removed from the position 0 to 4.

//... C Language program to implement basic operations on a Circular Queue
# include < stdio.h >
# include < conio.h >
# define max 10
void main()
{
	int cqueue[max], data;
	int front, rear, reply, option;
	clrscr();
	//... Initialise Circular Queue
	front = rear = 0;
	do
	{
		printf("\n C Language program to implement basic operations on a Circular Queue \n");
		printf("\n 1. Insert number in a Circular Queue");
		printf("\n 2 .Delete number from Circular Queue");
		printf("\n 3. Exit \n");
		printf("\n Select proper option ( 1 / 2 / 3 ) : ");
		scanf("%d", &option);
		switch(option)
		{
			case 1 : // insert
				printf("\n Enter number: ");
				scanf("%d", &data);
				reply = insq(cqueue, &front, &rear, &data);
				if(reply == -1)
					printf("\n Circular Queue is Full \n");
				else
					printf("\n Number %d is inserted in a Circular Queue \n", data);
				break;
			case 2 : // delete
				reply = delq(cqueue, &front, &rear,&data);
				if(reply == -1)
					printf("\n Circular Queue is Empty \n");
				else
					printf("\n %d is deleted from Circular Queue \n", data);
					printf("\n");
				break;
			case 3 : exit(0);
		} // switch
	}while(1);
} // main
int insq(int cqueue[max], int *front, int *rear, int *data)
{
	if((*rear + 1) % max == *front)
		return(-1);
	else
	{
		*rear = (*rear + 1) % max;
		cqueue[*rear] = *data;
		return(1);
	} // else
} // insq
int delq(int cqueue[max], int *front, int *rear, int *data)
{
	if(*front == *rear)
		return(-1);
	else
	{
		*front = (*front + 1) % max;
		*data = cqueue[*front];
		return(1);
	} // else
} // delq