Package it.unimi.dsi.fastutil.bytes

Class ByteHeapIndirectPriorityQueue

java.lang.Object

it.unimi.dsi.fastutil.bytes.ByteHeapSemiIndirectPriorityQueue

it.unimi.dsi.fastutil.bytes.ByteHeapIndirectPriorityQueue

All Implemented Interfaces:

ByteIndirectPriorityQueue, it.unimi.dsi.fastutil.IndirectPriorityQueue<java.lang.Byte>

public class ByteHeapIndirectPriorityQueue
extends ByteHeapSemiIndirectPriorityQueue

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 ByteHeapSemiIndirectPriorityQueue.trim() method to reduce its size, if necessary.

Implementation Specification:

This implementation does not allow one to enqueue several times the same index.

Constructor Summary

Constructors

Constructor	Description
ByteHeapIndirectPriorityQueue(byte[] refArray)	Creates a new empty queue with capacity equal to the length of the reference array and using the natural order.
ByteHeapIndirectPriorityQueue(byte[] refArray, int capacity)	Creates a new empty queue with a given capacity and using the natural order.
ByteHeapIndirectPriorityQueue(byte[] refArray, int[] a)	Wraps a given array in a queue using the natural order.
ByteHeapIndirectPriorityQueue(byte[] refArray, int[] a, int size)	Wraps a given array in a queue using the natural order.
ByteHeapIndirectPriorityQueue(byte[] refArray, int[] a, int size, ByteComparator c)	Wraps a given array in a queue using a given comparator.
ByteHeapIndirectPriorityQueue(byte[] refArray, int[] a, ByteComparator c)	Wraps a given array in a queue using a given comparator.
ByteHeapIndirectPriorityQueue(byte[] refArray, int capacity, ByteComparator c)	Creates a new empty queue with a given capacity and comparator.
ByteHeapIndirectPriorityQueue(byte[] refArray, ByteComparator c)	Creates a new empty queue with capacity equal to the length of the reference array and a given comparator.

Method Summary

Modifier and Type	Method	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.bytes.ByteHeapSemiIndirectPriorityQueue

comparator, first, front, size, toString, trim

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

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

isEmpty, last

Constructor Details

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] refArray,
int capacity,
ByteComparator 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] refArray,
ByteComparator 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] refArray,
int[] a,
int size,
ByteComparator 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] refArray,
int[] a,
ByteComparator 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] 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.

ByteHeapIndirectPriorityQueue

public ByteHeapIndirectPriorityQueue(byte[] 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 Details

enqueue

public void enqueue(int x)

Specified by:

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

Overrides:

enqueue in class ByteHeapSemiIndirectPriorityQueue

contains

public boolean contains(int index)

dequeue

public int dequeue()

Specified by:

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

Overrides:

dequeue in class ByteHeapSemiIndirectPriorityQueue

changed

public void changed()

Description copied from class: ByteHeapSemiIndirectPriorityQueue

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.Byte>

Overrides:

changed in class ByteHeapSemiIndirectPriorityQueue

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.Byte>

Overrides:

allChanged in class ByteHeapSemiIndirectPriorityQueue

remove

public boolean remove(int index)

clear

public void clear()

Specified by:

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

Overrides:

clear in class ByteHeapSemiIndirectPriorityQueue