it.unimi.dsi.fastutil.doubles

Class DoubleHeapIndirectPriorityQueue

java.lang.Object

it.unimi.dsi.fastutil.doubles.DoubleHeapSemiIndirectPriorityQueue

it.unimi.dsi.fastutil.doubles.DoubleHeapIndirectPriorityQueue

All Implemented Interfaces:

DoubleIndirectPriorityQueue, it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

public class DoubleHeapIndirectPriorityQueue
extends DoubleHeapSemiIndirectPriorityQueue

A type-specific heap-based indirect priority queue.

Instances of this class use an additional inversion array, of the same length of the reference array, to keep track of the heap position containing a given element of the reference array. The priority queue is represented using a heap. The heap is enlarged as needed, but it is never shrunk. Use the DoubleHeapSemiIndirectPriorityQueue.trim() method to reduce its size, if necessary.

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	inv The inversion array.

Fields inherited from class it.unimi.dsi.fastutil.doubles.DoubleHeapSemiIndirectPriorityQueue

c, heap, refArray, size

Constructor Summary

Constructors

Constructor and Description
DoubleHeapIndirectPriorityQueue(double[] refArray) Creates a new empty queue with capacity equal to the length of the reference array and using the natural order.
DoubleHeapIndirectPriorityQueue(double[] refArray, it.unimi.dsi.fastutil.doubles.DoubleComparator c) Creates a new empty queue with capacity equal to the length of the reference array and a given comparator.
DoubleHeapIndirectPriorityQueue(double[] refArray, int capacity) Creates a new empty queue with a given capacity and using the natural order.
DoubleHeapIndirectPriorityQueue(double[] refArray, int[] a) Wraps a given array in a queue using the natural order.
DoubleHeapIndirectPriorityQueue(double[] refArray, int[] a, it.unimi.dsi.fastutil.doubles.DoubleComparator c) Wraps a given array in a queue using a given comparator.
DoubleHeapIndirectPriorityQueue(double[] refArray, int[] a, int size) Wraps a given array in a queue using the natural order.
DoubleHeapIndirectPriorityQueue(double[] refArray, int[] a, int size, it.unimi.dsi.fastutil.doubles.DoubleComparator c) Wraps a given array in a queue using a given comparator.
DoubleHeapIndirectPriorityQueue(double[] refArray, int capacity, it.unimi.dsi.fastutil.doubles.DoubleComparator c) Creates a new empty queue with a given capacity and comparator.

Method Summary

Modifier and Type	Method and Description
void	allChanged() Rebuilds this queue in a bottom-up fashion (in linear time).
void	changed()
void	changed(int index)
void	clear()
boolean	contains(int index)
int	dequeue()
void	enqueue(int x)
boolean	remove(int index)

Methods inherited from class it.unimi.dsi.fastutil.doubles.DoubleHeapSemiIndirectPriorityQueue

comparator, ensureElement, first, front, size, toString, trim

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

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

isEmpty, last

Field Detail

inv

protected final int[] inv

The inversion array.

Constructor Detail

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int capacity,
                                       it.unimi.dsi.fastutil.doubles.DoubleComparator c)

Creates a new empty queue with a given capacity and comparator.

Parameters:

refArray - the reference array.

capacity - the initial capacity of this queue.

c - the comparator used in this queue, or null for the natural order.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int capacity)

Creates a new empty queue with a given capacity and using the natural order.

Parameters:

refArray - the reference array.

capacity - the initial capacity of this queue.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       it.unimi.dsi.fastutil.doubles.DoubleComparator c)

Creates a new empty queue with capacity equal to the length of the reference array and a given comparator.

Parameters:

refArray - the reference array.

c - the comparator used in this queue, or null for the natural order.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray)

Creates a new empty queue with capacity equal to the length of the reference array and using the natural order.

Parameters:

refArray - the reference array.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int[] a,
                                       int size,
                                       it.unimi.dsi.fastutil.doubles.DoubleComparator 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. The first size element of the array will be rearranged so to form a heap (this is more efficient than enqueing the elements of a one by one).

Parameters:

refArray - the reference array.

a - an array of indices into refArray.

size - the number of elements to be included in the queue.

c - the comparator used in this queue, or null for the natural order.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int[] a,
                                       it.unimi.dsi.fastutil.doubles.DoubleComparator 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. The elements of the array will be rearranged so to form a heap (this is more efficient than enqueing the elements of a one by one).

Parameters:

refArray - the reference array.

a - an array of indices into refArray.

c - the comparator used in this queue, or null for the natural order.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int[] 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. The first size element of the array will be rearranged so to form a heap (this is more efficient than enqueing the elements of a one by one).

Parameters:

refArray - the reference array.

a - an array of indices into refArray.

size - the number of elements to be included in the queue.

DoubleHeapIndirectPriorityQueue

public DoubleHeapIndirectPriorityQueue(double[] refArray,
                                       int[] 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. The elements of the array will be rearranged so to form a heap (this is more efficient than enqueing the elements of a one by one).

Parameters:

refArray - the reference array.

a - an array of indices into refArray.

Method Detail

enqueue

public void enqueue(int x)

Specified by:

enqueue in interface it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

Overrides:

enqueue in class DoubleHeapSemiIndirectPriorityQueue

contains

public boolean contains(int index)

dequeue

public int dequeue()

Specified by:

dequeue in interface it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

Overrides:

dequeue in class DoubleHeapSemiIndirectPriorityQueue

changed

public void changed()

Description copied from class: DoubleHeapSemiIndirectPriorityQueue

The caller must guarantee that when this method is called the index of the first element appears just once in the queue. Failure to do so will bring the queue in an inconsistent state, and will cause unpredictable behaviour.

Specified by:

changed in interface it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

Overrides:

changed in class DoubleHeapSemiIndirectPriorityQueue

changed

public void changed(int index)

allChanged

public void allChanged()

Rebuilds this queue in a bottom-up fashion (in linear time).

Specified by:

allChanged in interface it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

Overrides:

allChanged in class DoubleHeapSemiIndirectPriorityQueue

remove

public boolean remove(int index)

clear

public void clear()

Specified by:

clear in interface it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Double>

Overrides:

clear in class DoubleHeapSemiIndirectPriorityQueue