Class LongHeapIndirectPriorityQueue

java.lang.Object
it.unimi.dsi.fastutil.longs.LongHeapSemiIndirectPriorityQueue
it.unimi.dsi.fastutil.longs.LongHeapIndirectPriorityQueue
All Implemented Interfaces:
IndirectPriorityQueue<Long>, LongIndirectPriorityQueue

public class LongHeapIndirectPriorityQueue extends LongHeapSemiIndirectPriorityQueue
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 LongHeapSemiIndirectPriorityQueue.trim() method to reduce its size, if necessary.

Implementation Specification:
This implementation does not allow one to enqueue several times the same index.
  • Constructor Details

    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] refArray, int capacity, LongComparator 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] refArray, LongComparator 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] refArray, int[] 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. 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] refArray, int[] 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. 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] 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.
    • LongHeapIndirectPriorityQueue

      public LongHeapIndirectPriorityQueue(long[] 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