Queue : Array Implementation in C

#include <stdio.h>
#define QUEUE_LENGTH 50
struct queue
{
    int element[QUEUE_LENGTH];
    int front,rear,choice,x,y;
};
void traverse(struct queue q)
 {  printf("The elements of the queue are\n");
     for(int i=0;i<=q.rear;i++)
     {
         printf("%d\n",q.element[i]);
     }
 }
void add(struct queue *p,int y)
{
    if((*p).rear<QUEUE_LENGTH)
    {   (*p).rear +=1;
        (*p).element[(*p).rear]=y;
        printf("rear =  %d\n",(*p).rear);
        printf("type -1 to exit\n");
        scanf("%d",&y);
        if(y==(-1))
        {
            return;
        }
        add(p,y);
    }
    else
    {
        printf("Queue overflow\n");
    }
}
void delete(struct queue *p)
{
    int x=0,y=0;
    if((*p).front>(*p).rear)
    {
        printf("Queue empty\n");
    }
    else
    {
        x=(*p).element[(*p).front];
        (*p).element[(*p).front]=0;
        (*p).front=(*p).front+ 1;
    }
    printf("type 1 to delete or 2 to exit\n");
        scanf("%d",&y);
        if(y==(2))
        {
            return ;
        }
        if(y==(1))
        {
            traverse(*p);
            printf("%d is deleted\n",(*p).element[(*p).front]-1);
            delete(p);

        }
}
int main()
{   int choice=0,x=0;
    struct queue q;
    q.rear= -1,q.front=0;
        printf("\nEnter element to be added:\n");
        scanf("%d",&x);
        add(&q,x);
        traverse(q);
        delete(&q);
        printf("Deletion completed \n");
    return 0;
}

Output:

$gcc -o main *.c
$main
 
Enter element to be added:
1
rear =  0
type -1 to exit
2
rear =  1
type -1 to exit
3
rear =  2
type -1 to exit
4
rear =  3
type -1 to exit
5
rear =  4
type -1 to exit
6
rear =  5
type -1 to exit
7
rear =  6
type -1 to exit
-1
The elements of the queue are
1
2
3
4
5
6
7
type 1 to delete or 2 to exit
The elements of the queue are
0
2
3
4
5
6
7
1 is deleted
type 1 to delete or 2 to exit
The elements of the queue are
0
0
3
4
5
6
7
2 is deleted
type 1 to delete or 2 to exit
The elements of the queue are
0
0
0
4
5
6
7
3 is deleted
type 1 to delete or 2 to exit
Deletion completed 

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