All Downloads are FREE. Search and download functionalities are using the official Maven repository.

drv.HeapIndirectPriorityQueue.drv Maven / Gradle / Ivy

Go to download

fastutil extends the Java Collections Framework by providing type-specific maps, sets, lists and priority queues with a small memory footprint and fast access and insertion; provides also big (64-bit) arrays, sets and lists, and fast, practical I/O classes for binary and text files.

There is a newer version: 8.5.15
Show newest version
/*
 * Copyright (C) 2003-2017 Paolo Boldi and Sebastiano Vigna
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package PACKAGE;

#if KEY_CLASS_Object
import java.util.Comparator;
#endif

import it.unimi.dsi.fastutil.ints.IntArrays;

import java.util.Arrays;
import java.util.NoSuchElementException;

/** 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 {@link #trim()} method to reduce its size, if necessary. * *

This implementation does not allow one to enqueue several times the same index. */ public class HEAP_INDIRECT_PRIORITY_QUEUE KEY_GENERIC extends HEAP_SEMI_INDIRECT_PRIORITY_QUEUE KEY_GENERIC { /** The inversion array. */ protected final int inv[]; /** Creates a new empty queue with a given capacity and comparator. * * @param refArray the reference array. * @param capacity the initial capacity of this queue. * @param c the comparator used in this queue, or {@code null} for the natural order. */ public HEAP_INDIRECT_PRIORITY_QUEUE(KEY_GENERIC_TYPE[] refArray, int capacity, KEY_COMPARATOR KEY_SUPER_GENERIC c) { super(refArray, capacity, c); if (capacity > 0) this.heap = new int[capacity]; this.c = c; this.inv = new int[refArray.length]; Arrays.fill(inv, -1); } /** Creates a new empty queue with a given capacity and using the natural order. * * @param refArray the reference array. * @param capacity the initial capacity of this queue. */ public HEAP_INDIRECT_PRIORITY_QUEUE(KEY_GENERIC_TYPE[] refArray, int capacity) { this(refArray, capacity, null); } /** Creates a new empty queue with capacity equal to the length of the reference array and a given comparator. * * @param refArray the reference array. * @param c the comparator used in this queue, or {@code null} for the natural order. */ public HEAP_INDIRECT_PRIORITY_QUEUE(KEY_GENERIC_TYPE[] refArray, KEY_COMPARATOR KEY_SUPER_GENERIC c) { this(refArray, refArray.length, c); } /** Creates a new empty queue with capacity equal to the length of the reference array and using the natural order. * @param refArray the reference array. */ public HEAP_INDIRECT_PRIORITY_QUEUE(KEY_GENERIC_TYPE[] refArray) { this(refArray, refArray.length, null); } /** 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). * * @param refArray the reference array. * @param a an array of indices into refArray. * @param size the number of elements to be included in the queue. * @param c the comparator used in this queue, or {@code null} for the natural order. */ public HEAP_INDIRECT_PRIORITY_QUEUE(final KEY_GENERIC_TYPE[] refArray, final int[] a, final int size, final KEY_COMPARATOR KEY_SUPER_GENERIC c) { this(refArray, 0, c); this.heap = a; this.size = size; int i = size; while(i-- != 0) { if (inv[a[i]] != -1) throw new IllegalArgumentException("Index " + a[i] + " appears twice in the heap"); inv[a[i]] = i; } INDIRECT_HEAPS.makeHeap(refArray, a, inv, size, 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). * * @param refArray the reference array. * @param a an array of indices into refArray. * @param c the comparator used in this queue, or {@code null} for the natural order. */ public HEAP_INDIRECT_PRIORITY_QUEUE(final KEY_GENERIC_TYPE[] refArray, final int[] a, final KEY_COMPARATOR KEY_SUPER_GENERIC c) { this(refArray, a, a.length, c); } /** 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). * * @param refArray the reference array. * @param a an array of indices into refArray. * @param size the number of elements to be included in the queue. */ public HEAP_INDIRECT_PRIORITY_QUEUE(final KEY_GENERIC_TYPE[] refArray, final int[] a, int size) { this(refArray, a, size, null); } /** 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). * * @param refArray the reference array. * @param a an array of indices into refArray. */ public HEAP_INDIRECT_PRIORITY_QUEUE(final KEY_GENERIC_TYPE[] refArray, final int[] a) { this(refArray, a, a.length); } @Override public void enqueue(final int x) { if (inv[x] >= 0) throw new IllegalArgumentException("Index " + x + " belongs to the queue"); if (size == heap.length) heap = IntArrays.grow(heap, size + 1); inv[heap[size] = x] = size++; INDIRECT_HEAPS.upHeap(refArray, heap, inv, size, size - 1, c); } @Override public boolean contains(final int index) { return inv[index] >= 0; } @Override public int dequeue() { if (size == 0) throw new NoSuchElementException(); final int result = heap[0]; if (--size != 0) inv[heap[0] = heap[size]] = 0; inv[result] = -1; if (size != 0) INDIRECT_HEAPS.downHeap(refArray, heap, inv, size, 0, c); return result; } @Override public void changed() { INDIRECT_HEAPS.downHeap(refArray, heap, inv, size, 0, c); } @Override public void changed(final int index) { final int pos = inv[index]; if (pos < 0) throw new IllegalArgumentException("Index " + index + " does not belong to the queue"); final int newPos = INDIRECT_HEAPS.upHeap(refArray, heap, inv, size, pos, c); INDIRECT_HEAPS.downHeap(refArray, heap, inv, size, newPos, c); } /** Rebuilds this queue in a bottom-up fashion (in linear time). */ public void allChanged() { INDIRECT_HEAPS.makeHeap(refArray, heap, inv, size, c); } @Override public boolean remove(final int index) { final int result = inv[index]; if (result < 0) return false; inv[index] = -1; if (result < --size) { inv[heap[result] = heap[size]] = result; final int newPos = INDIRECT_HEAPS.upHeap(refArray, heap, inv, size, result, c); INDIRECT_HEAPS.downHeap(refArray, heap, inv, size, newPos, c); } return true; } @Override public void clear() { size = 0; Arrays.fill(inv, -1); } #ifdef TEST /** The original class, now just used for testing. */ private static class TestQueue { /** The reference array */ private KEY_TYPE refArray[]; /** Its length */ private int N; /** The number of elements in the heaps */ private int n; /** The two comparators */ private KEY_COMPARATOR primaryComp, secondaryComp; /** Two indirect heaps are used, called primary and secondary. Each of them contains a permutation of n among the indices 0, 1, ..., N-1 in such a way that the corresponding objects be sorted with respect to the two comparators. We also need an array inSec[] so that inSec[k] is the index of secondary containing k. */ private int primary[], secondary[], inSec[]; /** Builds a double indirect priority queue. * @param refArray The reference array. * @param primaryComp The primary comparator. * @param secondaryComp The secondary comparator. */ public TestQueue(KEY_TYPE refArray[], KEY_COMPARATOR primaryComp, KEY_COMPARATOR secondaryComp) { this.refArray = refArray; this.N = refArray.length; assert this.N != 0; this.n = 0; this.primaryComp = primaryComp; this.secondaryComp = secondaryComp; this.primary = new int[N]; this.secondary = new int[N]; this.inSec = new int[N]; java.util.Arrays.fill(inSec, -1); } /** Adds an index to the queue. Notice that the index should not be already present in the queue. * @param i The index to be added */ public void add(int i) { if (i < 0 || i >= refArray.length) throw new IndexOutOfBoundsException(); if (inSec[i] >= 0) throw new IllegalArgumentException(); primary[n] = i; secondary[n] = i; inSec[i] = n; n++; swimPrimary(n-1); swimSecondary(n-1); } /** Heapify the primary heap. * @param i The index of the heap to be heapified. */ private void heapifyPrimary(int i) { int dep = primary[i]; int child; while ((child = 2*i+1) < n) { if (child+1 < n && primaryComp.compare(refArray[primary[child+1]], refArray[primary[child]]) < 0) child++; if (primaryComp.compare(refArray[dep], refArray[primary[child]]) <= 0) break; primary[i] = primary[child]; i = child; } primary[i] = dep; } /** Heapify the secondary heap. * @param i The index of the heap to be heapified. */ private void heapifySecondary(int i) { int dep = secondary[i]; int child; while ((child = 2*i+1) < n) { if (child+1 < n && secondaryComp.compare(refArray[secondary[child+1]], refArray[secondary[child]]) < 0) child++; if (secondaryComp.compare(refArray[dep], refArray[secondary[child]]) <= 0) break; secondary[i] = secondary[child]; inSec[secondary[i]] = i; i = child; } secondary[i] = dep; inSec[secondary[i]] = i; } /** Swim and heapify the primary heap. * @param i The index to be moved. */ private void swimPrimary(int i) { int dep = primary[i]; int parent; while (i != 0 && (parent = (i - 1) / 2) >= 0) { if (primaryComp.compare(refArray[primary[parent]], refArray[dep]) <= 0) break; primary[i] = primary[parent]; i = parent; } primary[i] = dep; heapifyPrimary(i); } /** Swim and heapify the secondary heap. * @param i The index to be moved. */ private void swimSecondary(int i) { int dep = secondary[i]; int parent; while (i != 0 && (parent = (i - 1) / 2) >= 0) { if (secondaryComp.compare(refArray[secondary[parent]], refArray[dep]) <= 0) break; secondary[i] = secondary[parent]; inSec[secondary[i]] = i; i = parent; } secondary[i] = dep; inSec[secondary[i]] = i; heapifySecondary(i); } /** Returns the minimum element with respect to the primary comparator. @return the minimum element. */ public int top() { if (n == 0) throw new java.util.NoSuchElementException(); return primary[0]; } /** Returns the minimum element with respect to the secondary comparator. @return the minimum element. */ public int secTop() { if (n == 0) throw new java.util.NoSuchElementException(); return secondary[0]; } /** Removes the minimum element with respect to the primary comparator. * @return the removed element. */ public boolean remove() { if (n == 0) throw new java.util.NoSuchElementException(); if (inSec[primary[0]] == -1) return false; int result = primary[0]; int ins = inSec[result]; inSec[result] = -1; // Copy a leaf primary[0] = primary[n-1]; if (ins == n-1) { n--; heapifyPrimary(0); return true; } secondary[ins] = secondary[n-1]; inSec[secondary[ins]] = ins; // Heapify n--; heapifyPrimary(0); swimSecondary(ins); return true; } public void clear() { while(size() != 0) remove(); } public void remove(int index) { if (index >= refArray.length) throw new IndexOutOfBoundsException(); if (inSec[index] == -1) return; int ins = inSec[index]; inSec[index] = -1; // Copy a leaf primary[ins] = primary[n-1]; if (ins == n-1) { n--; swimPrimary(ins); return; } secondary[ins] = secondary[n-1]; inSec[secondary[ins]] = ins; // Heapify n--; swimPrimary(ins); swimSecondary(ins); } /** Signals that the minimum element with respect to the comparator has changed. */ public void change() { if (n == 0) throw new java.util.NoSuchElementException(); if (inSec[primary[0]] == -1) throw new IllegalArgumentException(); int ins = inSec[primary[0]]; heapifyPrimary(0); swimSecondary(ins); } public void change(int index) { if (index >= refArray.length) throw new IndexOutOfBoundsException(); if (inSec[index] == -1) throw new IllegalArgumentException(); if (n == 0) throw new java.util.NoSuchElementException(); int ins = inSec[index]; swimPrimary(ins); swimSecondary(ins); } /** Returns the number of elements in the queue. * @return the size of the queue */ public int size() { return n; } public String toString() { String s = "["; for (int i = 0; i < n; i++) s += refArray[primary[i]]+", "; return s+ "]"; } } private static long seed = System.currentTimeMillis(); private static java.util.Random r = new java.util.Random(seed); private static KEY_TYPE genKey() { #if KEY_CLASS_Byte || KEY_CLASS_Short || KEY_CLASS_Character return (KEY_TYPE)(r.nextInt()); #elif KEYS_PRIMITIVE return r.NEXT_KEY(); #elif KEY_CLASS_Object return Integer.toBinaryString(r.nextInt()); #else return new java.io.Serializable() {}; #endif } private static java.text.NumberFormat format = new java.text.DecimalFormat("#,###.00"); private static java.text.FieldPosition p = new java.text.FieldPosition(0); private static String format(double d) { StringBuffer s = new StringBuffer(); return format.format(d, s, p).toString(); } private static void speedTest(int n, boolean comp) { System.out.println("There are presently no speed tests for this class."); } private static void fatal(String msg) { System.out.println(msg); System.exit(1); } private static void ensure(boolean cond, String msg) { if (cond) return; fatal(msg); } private static boolean heapEqual(int[] a, int[] b, int sizea, int sizeb) { if (sizea != sizeb) return false; while(sizea-- != 0) if (a[sizea] != b[sizea]) return false; return true; } private static boolean invEqual(int inva[], int[] invb) { int i = inva.length; while(i-- != 0) if (inva[i] != invb[i]) return false; return true; } protected static void test(int n) { long ms; Exception mThrowsIllegal, tThrowsIllegal, mThrowsOutOfBounds, tThrowsOutOfBounds, mThrowsNoElement, tThrowsNoElement; int rm = 0, rt = 0; KEY_TYPE[] refArray = new KEY_TYPE[n]; for(int i = 0; i < n; i++) refArray[i] = genKey(); HEAP_INDIRECT_PRIORITY_QUEUE m = new HEAP_INDIRECT_PRIORITY_QUEUE(refArray, COMPARATORS.NATURAL_COMPARATOR); TestQueue t = new TestQueue(refArray, COMPARATORS.NATURAL_COMPARATOR, COMPARATORS.NATURAL_COMPARATOR); /* We add pairs to t. */ for(int i = 0; i < n / 2; i++) { t.add(i); m.enqueue(i); } ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after creation (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after creation (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); /* Now we add and remove random data in m and t, checking that the result is the same. */ for(int i=0; i<2*n; i++) { if (r.nextDouble() < 0.01) { t.clear(); m.clear(); for(int j = 0; j < n / 2; j++) { t.add(j); m.enqueue(j); } } int T = r.nextInt(2 * n); mThrowsNoElement = tThrowsNoElement = mThrowsOutOfBounds = tThrowsOutOfBounds = mThrowsIllegal = tThrowsIllegal = null; try { m.enqueue(T); } catch (IndexOutOfBoundsException e) { mThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { mThrowsIllegal = e; } try { t.add(T); } catch (IndexOutOfBoundsException e) { tThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { tThrowsIllegal = e; } ensure((mThrowsOutOfBounds == null) == (tThrowsOutOfBounds == null), "Error (" + seed + "): enqueue() divergence in IndexOutOfBoundsException for " + T + " (" + mThrowsOutOfBounds + ", " + tThrowsOutOfBounds + ")"); ensure((mThrowsIllegal == null) == (tThrowsIllegal == null), "Error (" + seed + "): enqueue() divergence in IllegalArgumentException for " + T + " (" + mThrowsIllegal + ", " + tThrowsIllegal + ")"); ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after enqueue (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after enqueue (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); if (m.size() != 0) { ensure(m.first() == t.top(), "Error (" + seed + "): m and t differ in first element after enqueue (" + m.first() + ", " + t.top() + ")"); } mThrowsNoElement = tThrowsNoElement = mThrowsOutOfBounds = tThrowsOutOfBounds = mThrowsIllegal = tThrowsIllegal = null; try { rm = m.dequeue(); } catch (IndexOutOfBoundsException e) { mThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { mThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { mThrowsNoElement = e; } try { rt = t.top(); t.remove(); } catch (IndexOutOfBoundsException e) { tThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { tThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { tThrowsNoElement = e; } ensure((mThrowsOutOfBounds == null) == (tThrowsOutOfBounds == null), "Error (" + seed + "): dequeue() divergence in IndexOutOfBoundsException (" + mThrowsOutOfBounds + ", " + tThrowsOutOfBounds + ")"); ensure((mThrowsIllegal == null) == (tThrowsIllegal == null), "Error (" + seed + "): dequeue() divergence in IllegalArgumentException (" + mThrowsIllegal + ", " + tThrowsIllegal + ")"); ensure((mThrowsNoElement == null) == (tThrowsNoElement == null), "Error (" + seed + "): dequeue() divergence in java.util.NoSuchElementException (" + mThrowsNoElement + ", " + tThrowsNoElement + ")"); if (mThrowsOutOfBounds == null) ensure(rt == rm , "Error (" + seed + "): divergence in dequeue() between t and m (" + rt + ", " + rm + ")"); ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after dequeue (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after dequeue (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); if (m.size() != 0) { ensure(m.first() == t.top(), "Error (" + seed + "): m and t differ in first element after dequeue (" + m.first() + ", " + t.top() + ")"); } int pos = r.nextInt(n * 2); try { m.remove(pos); } catch (IndexOutOfBoundsException e) { mThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { mThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { mThrowsNoElement = e; } try { t.remove(pos); } catch (IndexOutOfBoundsException e) { tThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { tThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { tThrowsNoElement = e; } ensure((mThrowsOutOfBounds == null) == (tThrowsOutOfBounds == null), "Error (" + seed + "): remove(int) divergence in IndexOutOfBoundsException (" + mThrowsOutOfBounds + ", " + tThrowsOutOfBounds + ")"); ensure((mThrowsIllegal == null) == (tThrowsIllegal == null), "Error (" + seed + "): remove(int) divergence in IllegalArgumentException (" + mThrowsIllegal + ", " + tThrowsIllegal + ")"); ensure((mThrowsNoElement == null) == (tThrowsNoElement == null), "Error (" + seed + "): remove(int) divergence in java.util.NoSuchElementException (" + mThrowsNoElement + ", " + tThrowsNoElement + ")"); if (mThrowsOutOfBounds == null) ensure(rt == rm , "Error (" + seed + "): divergence in remove(int) between t and m (" + rt + ", " + rm + ")"); ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after remove(int) (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after remove(int) (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); if (m.size() != 0) { ensure(m.first() == t.top(), "Error (" + seed + "): m and t differ in first element after remove(int) (" + m.first() + ", " + t.top() + ")"); } pos = r.nextInt(n * 2); try { m.changed(pos); } catch (IndexOutOfBoundsException e) { mThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { mThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { mThrowsNoElement = e; } try { t.change(pos); } catch (IndexOutOfBoundsException e) { tThrowsOutOfBounds = e; } catch (IllegalArgumentException e) { tThrowsIllegal = e; } catch (java.util.NoSuchElementException e) { tThrowsNoElement = e; } ensure((mThrowsOutOfBounds == null) == (tThrowsOutOfBounds == null), "Error (" + seed + "): change(int) divergence in IndexOutOfBoundsException (" + mThrowsOutOfBounds + ", " + tThrowsOutOfBounds + ")"); ensure((mThrowsIllegal == null) == (tThrowsIllegal == null), "Error (" + seed + "): change(int) divergence in IllegalArgumentException (" + mThrowsIllegal + ", " + tThrowsIllegal + ")"); ensure((mThrowsNoElement == null) == (tThrowsNoElement == null), "Error (" + seed + "): change(int) divergence in java.util.NoSuchElementException (" + mThrowsNoElement + ", " + tThrowsNoElement + ")"); if (mThrowsOutOfBounds == null) ensure(rt == rm , "Error (" + seed + "): divergence in change(int) between t and m (" + rt + ", " + rm + ")"); ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after change(int) (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after change(int) (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); if (m.size() != 0) { ensure(m.first() == t.top(), "Error (" + seed + "): m and t differ in first element after change(int) (" + m.first() + ", " + t.top() + ")"); } if (m.size() != 0) { refArray[m.first()] = genKey(); m.changed(); t.change(); ensure(heapEqual(m.heap, t.primary, m.size(), t.size()), "Error (" + seed + "): m and t differ after change (" + m + ", " + t + ")"); ensure(invEqual(m.inv, t.inSec), "Error (" + seed + "): m and t differ in inversion arrays after change (" + java.util.Arrays.toString(m.inv) + ", " + java.util.Arrays.toString(t.inSec) + ")"); if (m.size() != 0) { ensure(m.first() == t.top(), "Error (" + seed + "): m and t differ in first element after change (" + m.first() + ", " + t.top() + ")"); } } } /* Now we check that m actually holds the same data. */ m.clear(); ensure(m.isEmpty(), "Error (" + seed + "): m is not empty after clear()"); System.out.println("Test OK"); } public static void main(String args[]) { int n = Integer.parseInt(args[1]); if (args.length > 2) r = new java.util.Random(seed = Long.parseLong(args[2])); try { if ("speedTest".equals(args[0]) || "speedComp".equals(args[0])) speedTest(n, "speedComp".equals(args[0])); else if ("test".equals(args[0])) test(n); } catch(Throwable e) { e.printStackTrace(System.err); System.err.println("seed: " + seed); } } #endif }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy