/**
* Adds the item
* @param item the item to add
*/
public void enqueue(Item item) {
if (item == null)
throw new NullPointerException("null pointer not allowed");
if (size == a.length)
resize(2 * a.length); // double size of array
a[size++] = item;
}
/**
* Add the item
*
* @param item the item
*/
public void enqueue(Item item) {
if (item == null) throw new java.lang.NullPointerException();
// double the size of the array if necessary
if (N == a.length) resize(2 * a.length);
a[N++] = item;
}
/**
* add the item
*
* @param item the item
*/
public void enqueue(Item item) {
if (item == null) {
throw new NullPointerException("Item cannot be null.");
}
if (size == queue.length) {
resize(2 * size);
}
queue[size++] = item;
}
// return the number of items on the queue
public void enqueue(Item item) // add the item
{
if (item == null) throw new java.lang.NullPointerException();
if (size == arr.length) {
resize(size * 2);
}
arr[size] = item;
++size;
}
/** Add the item. Double size of array if necessary */
public void enqueue(Item item) {
if (item == null) {
throw new java.lang.NullPointerException();
}
if (this.size == a.length) {
resize(2 * a.length);
}
a[this.size++] = item;
}
/**
* Deletes and returns a random item on this queue.
*
* @return a random item on this queue
* @throw java.util.NoSuchElementException if this queue is empty
*/
public Item dequeue() {
if (isEmpty()) throw new NoSuchElementException("Queue underflow");
int rand = (int) (StdRandom.uniform() * N);
Item item = a[rand];
a[rand] = a[N - 1];
a[N - 1] = null;
N--;
if (N > 0 && N == a.length / 4) resize(a.length / 2);
return item;
}
/**
* remove and return a random item
*
* @return a random item
*/
public Item dequeue() {
if (size() == 0) {
throw new NoSuchElementException("Dequeue item from empty queue.");
}
int randomIndex = getRandomIndex();
Item result = queue[randomIndex];
queue[randomIndex] = queue[size - 1];
queue[size - 1] = null;
size--;
if (size > 0 && size == queue.length / 4) {
resize(queue.length / 2);
}
return result;
}
/**
* Remove and return a random item
* @return the removed item
*/
public Item dequeue() {
if (isEmpty())
throw new NoSuchElementException("Queue underflow");
int index = StdRandom.uniform(size);
Item item = a[index];
a[index] = a[size - 1];
a[size - 1] = null;
size--;
// shrink size of array if neccessary
if (size > 0 && size == a.length/4) resize(a.length / 2);
return item;
}
public Item dequeue() {
if (size == 0) throw new java.util.NoSuchElementException();
// StdRandom.shuffle(arr, 0, size- 1);
int randomN = StdRandom.uniform(size);
assert (size > 0);
Item item = arr[randomN];
swap(randomN, size - 1);
arr[size - 1] = null;
size--;
if (size > 0 && size == arr.length / 4) {
resize((arr.length) / 2);
}
return item;
}
/** remove and return a random item */
public Item dequeue() {
if (isEmpty()) {
throw new java.util.NoSuchElementException();
}
int index = StdRandom.uniform(this.size);
this.size--;
exchange(index, this.size);
Item item = this.a[this.size];
this.a[this.size] = null;
if (this.size > 0 && this.size == this.a.length / 4) {
resize(this.a.length / 2);
}
return item;
}
/**
* Remove and return a random item
*
* @return the random item
*/
public Item dequeue() {
if (N == 0) throw new java.util.NoSuchElementException();
int i = StdRandom.uniform(N);
exch(i, N - 1);
Item item = a[N - 1];
a[N - 1] = null; // don't loiter
N--;
if (N > 0 && N == a.length / 4) resize(a.length / 2);
return item;
}
public Item dequeue() // delete and return a random item
{
if (isEmpty()) throw new NoSuchElementException("Queue underflow");
// System.out.println("\t(dequeue) head="+head+"; "+"tail="+tail+"; N="+N+";
// capacity="+capacity());
Item value = a[head];
a[head] = null;
head++;
head %= a.length;
N--;
if (N > 0 && N == a.length / 4) resize(a.length / 2);
return value;
}
public void enqueue(Item item) // add the item
{
if (item == null) throw new NullPointerException();
// System.out.println("\t(enqueue="+item+") head="+head+"; "+"tail="+tail+"; N="+N+";
// capacity="+capacity());
a[tail] = item;
if (N > 0) {
int i = StdRandom.uniform(N + 1);
exchange(tail, (head + i) % a.length);
}
tail++;
tail %= a.length;
N++;
if (N == a.length) resize(2 * a.length);
}
/**
* Adds the item to this queue.
*
* @param item the item to add to this queue
* @throw java.util.NullPointerException if item is null
*/
public void enqueue(Item item) {
if (item == null) throw new NullPointerException("Cannot add null item");
if (N == a.length) resize(2 * a.length);
a[N++] = item;
}
/** Construct an empty randomized queue */
public RandomizedQueue() {
N = 0;
resize(2);
}
