Insert and delete operations over queue

Insert and delete operations are performed on queue whose size is 3. Queue follows FIFO format while performing insert and delete operation.First the front and rear is initialized to -1.New values are inserted at 0,1 and 2 position.While deleting the data ,the first inserted value is removed first i.e. the values are removed from 0,1 and 2 position.

#include < stdio.h >
#include < conio.h > 
#define max 3
void main()
{
	int queue[max],data;
	int front,rear,reply,option;	
	clrscr();
	//... init queue
	front = rear = -1;
	do
	{
		printf("\n 1. insert queue");
		printf("\n 2. delete queue");
		printf("\n 3. exit");
		printf("\nSelect proper option :");
		scanf("%d",&option);
		switch(option)
		{
			case 1 ://insert
			printf("\nEnter data : ");
			scanf("%d",&data);
			reply = insertq(queue,&rear,&data);
			if ( reply == - 1)
				printf("Queue is full");
			else
				printf("Inserted data in queue");
			break;
			case 2 : //dele
			reply = delq(queue,&front,&rear,&data);
			if ( reply == -1 )
				printf("Queue is empty ");
			else
				printf("Deleted data is : %d", data);
				break;
			case 3 : exit(0);
		} //switch
	} while(1);
} // main
int insertq ( int queue[max], int *rear , int *data)
{
	if ( *rear == max -1 )
		return(-1);
	else
	{
		*rear = *rear + 1;
		queue[*rear] = *data;
		return(1);
	} // else
} // insert
int delq( int queue[max], int *front, int *rear , int *data)
{
	if ( *front == *rear)
		return(-1);
	else
	{
		(*front)++;
		*data = queue[*front];
		return(1);
	} // else
} // insert