LongArrayPriorityQueue (fastutil 6.4.1 API)

java.lang.Object
- it.unimi.dsi.fastutil.AbstractPriorityQueue<Long>
- - it.unimi.dsi.fastutil.longs.AbstractLongPriorityQueue
  - - it.unimi.dsi.fastutil.longs.LongArrayPriorityQueue

All Implemented Interfaces:

LongPriorityQueue, PriorityQueue<Long>
```
public class LongArrayPriorityQueue
extends AbstractLongPriorityQueue
```
A type-specific array-based priority queue.
Instances of this class represent a priority queue using a backing array—all operations are performed directly on the array. The array is enlarged as needed, but it is never shrunk. Use the trim() method to reduce its size, if necessary.
This implementation is extremely inefficient, but it is difficult to beat when the size of the queue is very small.

Field Summary

Fields
Modifier and Type	Field and Description
`protected long[]`	`array` The backing array.
`protected LongComparator`	`c` The type-specific comparator used in this queue.
`protected int`	`size` The number of elements in this queue.

Constructor Summary

Constructors
Constructor and Description
`LongArrayPriorityQueue()` Creates a new empty queue using the natural order.
`LongArrayPriorityQueue(int capacity)` Creates a new empty queue with a given capacity and using the natural order.
`LongArrayPriorityQueue(int capacity, LongComparator c)` Creates a new empty queue with a given capacity and comparator.
`LongArrayPriorityQueue(long[] a)` Wraps a given array in a queue using the natural order.
`LongArrayPriorityQueue(long[] a, int size)` Wraps a given array in a queue using the natural order.
`LongArrayPriorityQueue(long[] a, int size, LongComparator c)` Wraps a given array in a queue using a given comparator.
`LongArrayPriorityQueue(long[] a, LongComparator c)` Wraps a given array in a queue using a given comparator.
`LongArrayPriorityQueue(LongComparator c)` Creates a new empty queue with a given comparator.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`changed()` Notifies the queue that the first element has changed (optional operation).
`void`	`clear()` Removes all elements from this queue.
`LongComparator`	`comparator()` Returns the comparator associated with this sorted set, or null if it uses its elements' natural ordering.
`long`	`dequeueLong()` Dequeues an element.
`void`	`enqueue(long x)` Enqueues a new element.
`long`	`firstLong()` Returns the first element of the queue.
`int`	`size()` Returns the number of elements in this queue.
`void`	`trim()` Trims the underlying array so that it has exactly `size()` elements.

Methods inherited from class it.unimi.dsi.fastutil.longs.AbstractLongPriorityQueue
dequeue, enqueue, first, last, lastLong

Methods inherited from class it.unimi.dsi.fastutil.AbstractPriorityQueue
isEmpty

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface it.unimi.dsi.fastutil.PriorityQueue
isEmpty

- Field Detail
  - array
```
protected long[] array
```
    The backing array.
  - size
```
protected int size
```
    The number of elements in this queue.
  - c
```
protected LongComparator c
```
    The type-specific comparator used in this queue.
- Constructor Detail
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(int capacity,
                      LongComparator c)
```
    Creates a new empty queue with a given capacity and comparator.
    
    Parameters:
    capacity - the initial capacity of this queue.
    c - the comparator used in this queue, or null for the natural order.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(int capacity)
```
    Creates a new empty queue with a given capacity and using the natural order.
    
    Parameters:
    capacity - the initial capacity of this queue.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(LongComparator c)
```
    Creates a new empty queue with a given comparator.
    
    Parameters:
    c - the comparator used in this queue, or null for the natural order.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue()
```
    Creates a new empty queue using the natural order.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(long[] a,
                      int size,
                      LongComparator c)
```
    Wraps a given array in a queue using a given comparator.
    The queue returned by this method will be backed by the given array.
    
    Parameters:
    a - an array.
    size - the number of elements to be included in the queue.
    c - the comparator used in this queue, or null for the natural order.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(long[] a,
                      LongComparator c)
```
    Wraps a given array in a queue using a given comparator.
    The queue returned by this method will be backed by the given array.
    
    Parameters:
    a - an array.
    c - the comparator used in this queue, or null for the natural order.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(long[] a,
                      int size)
```
    Wraps a given array in a queue using the natural order.
    The queue returned by this method will be backed by the given array.
    
    Parameters:
    a - an array.
    size - the number of elements to be included in the queue.
  - LongArrayPriorityQueue
```
public LongArrayPriorityQueue(long[] a)
```
    Wraps a given array in a queue using the natural order.
    The queue returned by this method will be backed by the given array.
    
    Parameters:
    a - an array.
- Method Detail
  - enqueue
```
public void enqueue(long x)
```
    Description copied from interface: LongPriorityQueue
    
    Enqueues a new element.
    
    Parameters:
    x - the element to enqueue.
  - dequeueLong
```
public long dequeueLong()
```
    Dequeues an element.
    Note that each call to this method requires a complete scan of the backing array. Please consider caching its result.
    
    Returns:
    the dequeued element.
  - firstLong
```
public long firstLong()
```
    Description copied from interface: LongPriorityQueue
    
    Returns the first element of the queue.
    
    Returns:
    the first element.
  - changed
```
public void changed()
```
    Description copied from interface: PriorityQueue
    
    Notifies the queue that the first element has changed (optional operation).
    
    Specified by:
    
    changed in interface PriorityQueue<Long>
    
    Overrides:
    
    changed in class AbstractPriorityQueue<Long>
  - size
```
public int size()
```
    Description copied from interface: PriorityQueue
    
    Returns the number of elements in this queue.
    
    Returns:
    the number of elements in this queue.
  - clear
```
public void clear()
```
    Description copied from interface: PriorityQueue
    
    Removes all elements from this queue.
  - trim
```
public void trim()
```
    Trims the underlying array so that it has exactly size() elements.
  - comparator
```
public LongComparator comparator()
```
    Description copied from interface: LongPriorityQueue
    
    Returns the comparator associated with this sorted set, or null if it uses its elements' natural ordering.
    Note that this specification strengthens the one given in PriorityQueue.comparator().
    
    Returns:
    the comparator associated with this sorted set, or null if it uses its elements' natural ordering.
    See Also:
    PriorityQueue.comparator()

Class LongArrayPriorityQueue

Field Summary

Constructor Summary

Method Summary

Methods inherited from class it.unimi.dsi.fastutil.longs.AbstractLongPriorityQueue

Methods inherited from class it.unimi.dsi.fastutil.AbstractPriorityQueue

Methods inherited from class java.lang.Object

Methods inherited from interface it.unimi.dsi.fastutil.PriorityQueue

Field Detail

array

size

c

Constructor Detail

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

LongArrayPriorityQueue

Method Detail

enqueue

dequeueLong

firstLong

changed

size

clear

trim

comparator