Class BinaryArrayBulkInsertWeakHeap<K>
- Type Parameters:
K
- the type of keys maintained by this heap
- All Implemented Interfaces:
Serializable
,Heap<K>
Comparator
provided at heap creation time, depending on which
constructor is used.
The implementation uses an array in order to store the elements and
automatically maintains the size of the array much like a
Vector
does, providing amortized O(1) time cost for the
insert
and amortized O(log(n)) for the deleteMin
operation.
Operation findMin
, is a worst-case O(1) operation.
Constructing such a heap from an array of elements can be performed using the
method heapify(Object[])
or heapify(Object[], Comparator)
in linear time.
Note that the ordering maintained by a binary heap, like any heap, and
whether or not an explicit comparator is provided, must be consistent
with equals
if this heap is to correctly implement the
Heap
interface. (See Comparable
or Comparator
for a
precise definition of consistent with equals.) This is so because
the Heap
interface is defined in terms of the equals
operation, but a binary heap performs all key comparisons using its
compareTo
(or compare
) method, so two keys that are deemed
equal by this method are, from the standpoint of the binary heap, equal. The
behavior of a heap is well-defined even if its ordering is
inconsistent with equals
; it just fails to obey the general contract
of the Heap
interface.
Note that this implementation is not synchronized. If multiple threads access a heap concurrently, and at least one of the threads modifies the heap structurally, it must be synchronized externally. (A structural modification is any operation that adds or deletes one or more elements or changing the key of some element.) This is typically accomplished by synchronizing on some object that naturally encapsulates the heap.
- See Also:
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Field Summary
FieldsModifier and TypeFieldDescriptionprotected static final int
Insertion buffer capacity for integer size since we are using Java arrays to store elements.protected K[]
The insertion bufferprotected int
Position of minimum in the insertion bufferprotected int
Number of elements in the insertion bufferprivate static final long
Fields inherited from class org.jheaps.array.BinaryArrayWeakHeap
DEFAULT_HEAP_CAPACITY, reverse
Fields inherited from class org.jheaps.array.AbstractArrayWeakHeap
array, comparator, DOWNSIZING_MIN_HEAP_CAPACITY, MAX_HEAP_CAPACITY, MIN_HEAP_CAPACITY, minCapacity, size
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Constructor Summary
ConstructorsConstructorDescriptionConstructs a new, empty heap, using the natural ordering of its keys.BinaryArrayBulkInsertWeakHeap
(int capacity) Constructs a new, empty heap, with a provided initial capacity using the natural ordering of its keys.BinaryArrayBulkInsertWeakHeap
(Comparator<? super K> comparator) Constructs a new, empty heap, ordered according to the given comparator.BinaryArrayBulkInsertWeakHeap
(Comparator<? super K> comparator, int capacity) Constructs a new, empty heap, with a provided initial capacity ordered according to the given comparator. -
Method Summary
Modifier and TypeMethodDescriptionprotected void
Bulk insert from insertion buffer into the weak heap.protected void
Bulk insert from insertion buffer into the weak heap.void
clear()
Clear all the elements of this heap.Delete and return an element with the minimum key.findMin()
Find an element with the minimum key.static <K> BinaryArrayBulkInsertWeakHeap<K>
heapify
(K[] array) Create a heap from an array of elements.static <K> BinaryArrayBulkInsertWeakHeap<K>
heapify
(K[] array, Comparator<? super K> comparator) Create a heap from an array of elements.void
Insert a key into the heap.protected boolean
Check if the bulk insertion buffer is full.boolean
isEmpty()
Returnstrue
if this heap is empty.long
size()
Returns the number of elements in this heap.Methods inherited from class org.jheaps.array.BinaryArrayWeakHeap
dancestor, ensureCapacity, fixdown, fixdownWithComparator, fixup, fixupWithComparator, initCapacity, join, joinWithComparator
Methods inherited from class org.jheaps.array.AbstractArrayWeakHeap
checkCapacity, comparator
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Field Details
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serialVersionUID
private static final long serialVersionUID- See Also:
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INSERTION_BUFFER_CAPACITY
protected static final int INSERTION_BUFFER_CAPACITYInsertion buffer capacity for integer size since we are using Java arrays to store elements.- See Also:
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insertionBuffer
The insertion buffer -
insertionBufferSize
protected int insertionBufferSizeNumber of elements in the insertion buffer -
insertionBufferMinPos
protected int insertionBufferMinPosPosition of minimum in the insertion buffer
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Constructor Details
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BinaryArrayBulkInsertWeakHeap
public BinaryArrayBulkInsertWeakHeap()Constructs a new, empty heap, using the natural ordering of its keys.All keys inserted into the heap must implement the
Comparable
interface. Furthermore, all such keys must be mutually comparable:k1.compareTo(k2)
must not throw aClassCastException
for any keysk1
andk2
in the heap. If the user attempts to put a key into the heap that violates this constraint (for example, the user attempts to put a string key into a heap whose keys are integers), theinsert(Object key)
call will throw aClassCastException
.The initial capacity of the heap is
BinaryArrayWeakHeap.DEFAULT_HEAP_CAPACITY
and adjusts automatically based on the sequence of insertions and deletions. -
BinaryArrayBulkInsertWeakHeap
public BinaryArrayBulkInsertWeakHeap(int capacity) Constructs a new, empty heap, with a provided initial capacity using the natural ordering of its keys.All keys inserted into the heap must implement the
Comparable
interface. Furthermore, all such keys must be mutually comparable:k1.compareTo(k2)
must not throw aClassCastException
for any keysk1
andk2
in the heap. If the user attempts to put a key into the heap that violates this constraint (for example, the user attempts to put a string key into a heap whose keys are integers), theinsert(Object key)
call will throw aClassCastException
.The initial capacity of the heap is provided by the user and is adjusted automatically based on the sequence of insertions and deletions.
- Parameters:
capacity
- the initial heap capacity
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BinaryArrayBulkInsertWeakHeap
Constructs a new, empty heap, ordered according to the given comparator.All keys inserted into the heap must be mutually comparable by the given comparator:
comparator.compare(k1, k2)
must not throw aClassCastException
for any keysk1
andk2
in the heap. If the user attempts to put a key into the heap that violates this constraint, theinsert(Object key)
call will throw aClassCastException
.The initial capacity of the heap is
BinaryArrayWeakHeap.DEFAULT_HEAP_CAPACITY
and adjusts automatically based on the sequence of insertions and deletions.- Parameters:
comparator
- the comparator that will be used to order this heap. Ifnull
, the natural ordering of the keys will be used.
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BinaryArrayBulkInsertWeakHeap
Constructs a new, empty heap, with a provided initial capacity ordered according to the given comparator.All keys inserted into the heap must be mutually comparable by the given comparator:
comparator.compare(k1, k2)
must not throw aClassCastException
for any keysk1
andk2
in the heap. If the user attempts to put a key into the heap that violates this constraint, theinsert(Object key)
call will throw aClassCastException
.The initial capacity of the heap is provided by the user and is adjusted automatically based on the sequence of insertions and deletions.
- Parameters:
comparator
- the comparator that will be used to order this heap. Ifnull
, the natural ordering of the keys will be used.capacity
- the initial heap capacity
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Method Details
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isEmpty
public boolean isEmpty()Returnstrue
if this heap is empty. -
size
public long size()Returns the number of elements in this heap. -
clear
public void clear()Clear all the elements of this heap. -
findMin
Find an element with the minimum key. -
insert
Insert a key into the heap. -
deleteMin
Delete and return an element with the minimum key. If multiple such elements exists, only one of them will be deleted. -
heapify
Create a heap from an array of elements. The elements of the array are not destroyed. The method has linear time complexity.- Type Parameters:
K
- the type of keys maintained by the heap- Parameters:
array
- an array of elements- Returns:
- a binary heap
- Throws:
IllegalArgumentException
- in case the array is null
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heapify
public static <K> BinaryArrayBulkInsertWeakHeap<K> heapify(K[] array, Comparator<? super K> comparator) Create a heap from an array of elements. The elements of the array are not destroyed. The method has linear time complexity.- Type Parameters:
K
- the type of keys maintained by the heap- Parameters:
array
- an array of elementscomparator
- the comparator to use- Returns:
- a binary heap
- Throws:
IllegalArgumentException
- in case the array is null
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isBulkInsertionBufferFull
protected boolean isBulkInsertionBufferFull()Check if the bulk insertion buffer is full.- Returns:
- true if the bulk insertion buffer is full, false otherwise
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bulkInsert
protected void bulkInsert()Bulk insert from insertion buffer into the weak heap. -
bulkInsertWithComparator
protected void bulkInsertWithComparator()Bulk insert from insertion buffer into the weak heap.
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