nate

// DO NOT MODIFY THIS STRUCTURE
struct dequeue {
  int front;
  int back;
  int len;
  int maxlen;
  int *queue;
};


struct dequeue *dequeue_create(void) {
  struct dequeue *dq = malloc(sizeof(int));
  dq->front = 0; //indexes
  dq->back = 2;
  dq->len = 1;
  dq->maxlen = 3;
  dq->queue = malloc(sizeof(int));
}


bool dequeue_is_empty(const struct dequeue *q) {
  assert(q);
  return (q->len == 0);
}


int dequeue_front(const struct dequeue *q) {
  assert(q);
  return q->front;
}


int dequeue_back(const struct dequeue *q) {
  assert(q);
  return q->back;
}

int dequeue_remove_front(struct dequeue *q) {
  assert(q);
  ++q->front;

  if (
}


int dequeue_remove_back(struct dequeue *q) {
  return 0;
}


// resize_up(q) consumes a dequeue q and puts the elements in q in the center of the array. This function should only be called after a realloc has been called on the array to modify its size
// effects: modifies q->queue and q->front
void resize_up(struct dequeue *q) {
  assert(q);
  int start = (q->maxlen / 3);

  for (int i = 0; i < q->len; ++i) {
    q->queue[start + i] = q->queue[q->front + i];
  }

  q->front = start;
  q->back = start + (len - 1);
}

void dequeue_add_front(int item, struct dequeue *q) {
  assert(q);
  --q->front;
  q->queue[q->front] = item;
  ++q->len;

  if (q->front == 0) {
    q->maxlen = (q->len * 3); //triple current length
    q->queue = realloc(q->queue, q->maxlen * sizeof(int));
    resize_up(q);
  }
}


void dequeue_add_back(int item, struct dequeue *q){
  ++q->back;
  q->queue[q->back] = item;
  ++q->len;

  if (q->back == (q->maxlen - 1)) {
    q->maxlen = (q->len * 3); //triple current length
    q->queue = realloc(q->queue, q->maxlen * sizeof(int));
    resize_up(q);
  }
}


void dequeue_destroy(struct dequeue *q) {

}