Queu_Pointer_Array

#include<stdio.h>

#define Q_SIZE 5

typedef struct{
    int data[Q_SIZE+1];
    int head;
    int tail;
}Queue;

void enqueue(Queue *q,int item)
{
    if((q->tail+1)%(Q_SIZE+1)==q->head){
        printf("Queue is full\n");
        return;
    }
    q->data[q->tail]=item;
    q->tail=(q->tail+1)%(Q_SIZE+1);
}

int dequeue(Queue *q)
{
    int item;
    if((q->tail)==q->head){
        printf("Queue is empty!!\n");
        return -1;
    }
    item=q->data[q->head];
    q->head=(q->head+1)%(Q_SIZE+1);

    return item;
}

int main()
{
    Queue my_q;
    int item;

    my_q.head=0;
    my_q.tail=0;

    enqueue(&my_q,10);
    printf("Tail:%d\n",my_q.tail);
    enqueue(&my_q,20);
    printf("Tail:%d\n",my_q.tail);
    enqueue(&my_q,30);
    printf("Tail:%d\n",my_q.tail);
    enqueue(&my_q,40);
    printf("Tail:%d\n",my_q.tail);
    enqueue(&my_q,50);
    printf("Tail:%d\n",my_q.tail);
    enqueue(&my_q,60);
    printf("Tail:%d\n\n",my_q.tail);

    printf("Beginning head:%d\n",my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
    item=dequeue(&my_q);
    printf("item = %d, head:%d\n",item,my_q.head);
}