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/*
* Copyright (C) 2002-2024 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 it.unimi.dsi.fastutil.ints;
import it.unimi.dsi.fastutil.objects.AbstractObjectSortedSet;
import it.unimi.dsi.fastutil.objects.ObjectBidirectionalIterator;
import it.unimi.dsi.fastutil.objects.ObjectListIterator;
import it.unimi.dsi.fastutil.objects.ObjectSortedSet;
import java.util.Comparator;
import java.util.Iterator;
import java.util.Map;
import java.util.SortedMap;
import java.util.NoSuchElementException;
/**
* A type-specific red-black tree map with a fast, small-footprint implementation.
*
*
* The iterators provided by the views of this class are type-specific
* {@linkplain it.unimi.dsi.fastutil.BidirectionalIterator bidirectional iterators}. Moreover, the
* iterator returned by {@code iterator()} can be safely cast to a type-specific
* {@linkplain java.util.ListIterator list iterator}.
*
*/
public class Int2IntRBTreeMap extends AbstractInt2IntSortedMap implements java.io.Serializable, Cloneable {
/** A reference to the root entry. */
protected transient Entry tree;
/** Number of entries in this map. */
protected int count;
/** The first key in this map. */
protected transient Entry firstEntry;
/** The last key in this map. */
protected transient Entry lastEntry;
/** Cached set of entries. */
protected transient ObjectSortedSet entries;
/** Cached set of keys. */
protected transient IntSortedSet keys;
/** Cached collection of values. */
protected transient IntCollection values;
/**
* The value of this variable remembers, after a {@code put()} or a {@code remove()}, whether the
* domain of the map has been modified.
*/
protected transient boolean modified;
/** This map's comparator, as provided in the constructor. */
protected Comparator storedComparator;
/**
* This map's actual comparator; it may differ from {@link #storedComparator} because it is always a
* type-specific comparator, so it could be derived from the former by wrapping.
*/
protected transient IntComparator actualComparator;
private static final long serialVersionUID = -7046029254386353129L;
{
allocatePaths();
}
/**
* Creates a new empty tree map.
*/
public Int2IntRBTreeMap() {
tree = null;
count = 0;
}
/**
* Generates the comparator that will be actually used.
*
*
* When a given {@link Comparator} is specified and stored in {@link #storedComparator}, we must
* check whether it is type-specific. If it is so, we can used directly, and we store it in
* {@link #actualComparator}. Otherwise, we adapt it using a helper static method.
*/
private void setActualComparator() {
actualComparator = IntComparators.asIntComparator(storedComparator);
}
/**
* Creates a new empty tree map with the given comparator.
*
* @param c a (possibly type-specific) comparator.
*/
public Int2IntRBTreeMap(final Comparator c) {
this();
storedComparator = c;
setActualComparator();
}
/**
* Creates a new tree map copying a given map.
*
* @param m a {@link Map} to be copied into the new tree map.
*/
public Int2IntRBTreeMap(final Map m) {
this();
putAll(m);
}
/**
* Creates a new tree map copying a given sorted map (and its {@link Comparator}).
*
* @param m a {@link SortedMap} to be copied into the new tree map.
*/
public Int2IntRBTreeMap(final SortedMap m) {
this(m.comparator());
putAll(m);
}
/**
* Creates a new tree map copying a given map.
*
* @param m a type-specific map to be copied into the new tree map.
*/
public Int2IntRBTreeMap(final Int2IntMap m) {
this();
putAll(m);
}
/**
* Creates a new tree map copying a given sorted map (and its {@link Comparator}).
*
* @param m a type-specific sorted map to be copied into the new tree map.
*/
public Int2IntRBTreeMap(final Int2IntSortedMap m) {
this(m.comparator());
putAll(m);
}
/**
* Creates a new tree map using the elements of two parallel arrays and the given comparator.
*
* @param k the array of keys of the new tree map.
* @param v the array of corresponding values in the new tree map.
* @param c a (possibly type-specific) comparator.
* @throws IllegalArgumentException if {@code k} and {@code v} have different lengths.
*/
public Int2IntRBTreeMap(final int[] k, final int v[], final Comparator c) {
this(c);
if (k.length != v.length) throw new IllegalArgumentException("The key array and the value array have different lengths (" + k.length + " and " + v.length + ")");
for (int i = 0; i < k.length; i++) this.put(k[i], v[i]);
}
/**
* Creates a new tree map using the elements of two parallel arrays.
*
* @param k the array of keys of the new tree map.
* @param v the array of corresponding values in the new tree map.
* @throws IllegalArgumentException if {@code k} and {@code v} have different lengths.
*/
public Int2IntRBTreeMap(final int[] k, final int v[]) {
this(k, v, null);
}
/*
* The following methods implements some basic building blocks used by
* all accessors. They are (and should be maintained) identical to those used in RBTreeSet.drv.
*
* The put()/remove() code is derived from Ben Pfaff's GNU libavl
* (https://adtinfo.org/). If you want to understand what's
* going on, you should have a look at the literate code contained therein
* first.
*/
/**
* Compares two keys in the right way.
*
*
* This method uses the {@link #actualComparator} if it is non-{@code null}. Otherwise, it resorts
* to primitive type comparisons or to {@link Comparable#compareTo(Object) compareTo()}.
*
* @param k1 the first key.
* @param k2 the second key.
* @return a number smaller than, equal to or greater than 0, as usual (i.e., when k1 < k2, k1 =
* k2 or k1 > k2, respectively).
*/
final int compare(final int k1, final int k2) {
return actualComparator == null ? (Integer.compare((k1), (k2))) : actualComparator.compare(k1, k2);
}
/**
* Returns the entry corresponding to the given key, if it is in the tree; {@code null}, otherwise.
*
* @param k the key to search for.
* @return the corresponding entry, or {@code null} if no entry with the given key exists.
*/
final Entry findKey(final int k) {
Entry e = tree;
int cmp;
while (e != null && (cmp = compare(k, e.key)) != 0) e = cmp < 0 ? e.left() : e.right();
return e;
}
/**
* Locates a key.
*
* @param k a key.
* @return the last entry on a search for the given key; this will be the given key, if it present;
* otherwise, it will be either the smallest greater key or the greatest smaller key.
*/
final Entry locateKey(final int k) {
Entry e = tree, last = tree;
int cmp = 0;
while (e != null && (cmp = compare(k, e.key)) != 0) {
last = e;
e = cmp < 0 ? e.left() : e.right();
}
return cmp == 0 ? e : last;
}
/**
* This vector remembers the path and the direction followed during the current insertion. It
* suffices for about 232 entries.
*/
private transient boolean dirPath[];
private transient Entry nodePath[];
private void allocatePaths() {
dirPath = new boolean[64];
nodePath = new Entry[64];
}
/**
* Adds an increment to value currently associated with a key.
*
*
* Note that this method respects the {@linkplain #defaultReturnValue() default return value}
* semantics: when called with a key that does not currently appears in the map, the key will be
* associated with the default return value plus the given increment.
*
* @param k the key.
* @param incr the increment.
* @return the old value, or the {@linkplain #defaultReturnValue() default return value} if no value
* was present for the given key.
*/
public int addTo(final int k, final int incr) {
Entry e = add(k);
final int oldValue = e.value;
e.value += incr;
return oldValue;
}
@Override
public int put(final int k, final int v) {
Entry e = add(k);
final int oldValue = e.value;
e.value = v;
return oldValue;
}
/**
* Returns a node with key k in the balanced tree, creating one with defRetValue if necessary.
*
* @param k the key
* @return a node with key k. If a node with key k already exists, then that node is returned,
* otherwise a new node with defRetValue is created ensuring that the tree is balanced after
* creation of the node.
*/
private Entry add(final int k) {
/* After execution of this method, modified is true iff a new entry has been inserted. */
modified = false;
int maxDepth = 0;
Entry e;
if (tree == null) { // The case of the empty tree is treated separately.
count++;
e = tree = lastEntry = firstEntry = new Entry(k, defRetValue);
} else {
Entry p = tree;
int cmp, i = 0;
while (true) {
if ((cmp = compare(k, p.key)) == 0) {
// We clean up the node path, or we could have stale references later.
while (i-- != 0) nodePath[i] = null;
return p;
}
nodePath[i] = p;
if (dirPath[i++] = cmp > 0) {
if (p.succ()) {
count++;
e = new Entry(k, defRetValue);
if (p.right == null) lastEntry = e;
e.left = p;
e.right = p.right;
p.right(e);
break;
}
p = p.right;
} else {
if (p.pred()) {
count++;
e = new Entry(k, defRetValue);
if (p.left == null) firstEntry = e;
e.right = p;
e.left = p.left;
p.left(e);
break;
}
p = p.left;
}
}
modified = true;
maxDepth = i--;
while (i > 0 && !nodePath[i].black()) {
if (!dirPath[i - 1]) {
Entry y = nodePath[i - 1].right;
if (!nodePath[i - 1].succ() && !y.black()) {
nodePath[i].black(true);
y.black(true);
nodePath[i - 1].black(false);
i -= 2;
} else {
Entry x;
if (!dirPath[i]) y = nodePath[i];
else {
x = nodePath[i];
y = x.right;
x.right = y.left;
y.left = x;
nodePath[i - 1].left = y;
if (y.pred()) {
y.pred(false);
x.succ(y);
}
}
x = nodePath[i - 1];
x.black(false);
y.black(true);
x.left = y.right;
y.right = x;
if (i < 2) tree = y;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = y;
else nodePath[i - 2].left = y;
}
if (y.succ()) {
y.succ(false);
x.pred(y);
}
break;
}
} else {
Entry y = nodePath[i - 1].left;
if (!nodePath[i - 1].pred() && !y.black()) {
nodePath[i].black(true);
y.black(true);
nodePath[i - 1].black(false);
i -= 2;
} else {
Entry x;
if (dirPath[i]) y = nodePath[i];
else {
x = nodePath[i];
y = x.left;
x.left = y.right;
y.right = x;
nodePath[i - 1].right = y;
if (y.succ()) {
y.succ(false);
x.pred(y);
}
}
x = nodePath[i - 1];
x.black(false);
y.black(true);
x.right = y.left;
y.left = x;
if (i < 2) tree = y;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = y;
else nodePath[i - 2].left = y;
}
if (y.pred()) {
y.pred(false);
x.succ(y);
}
break;
}
}
}
}
tree.black(true);
// We clean up the node path, or we could have stale references later.
while (maxDepth-- != 0) nodePath[maxDepth] = null;
return e;
}
/* After execution of this method, {@link #modified} is true iff an entry
has been deleted. */
@Override
public int remove(final int k) {
modified = false;
if (tree == null) return defRetValue;
Entry p = tree;
int cmp;
int i = 0;
final int kk = k;
while (true) {
if ((cmp = compare(kk, p.key)) == 0) break;
dirPath[i] = cmp > 0;
nodePath[i] = p;
if (dirPath[i++]) {
if ((p = p.right()) == null) {
// We clean up the node path, or we could have stale references later.
while (i-- != 0) nodePath[i] = null;
return defRetValue;
}
} else {
if ((p = p.left()) == null) {
// We clean up the node path, or we could have stale references later.
while (i-- != 0) nodePath[i] = null;
return defRetValue;
}
}
}
if (p.left == null) firstEntry = p.next();
if (p.right == null) lastEntry = p.prev();
if (p.succ()) {
if (p.pred()) {
if (i == 0) tree = p.left;
else {
if (dirPath[i - 1]) nodePath[i - 1].succ(p.right);
else nodePath[i - 1].pred(p.left);
}
} else {
p.prev().right = p.right;
if (i == 0) tree = p.left;
else {
if (dirPath[i - 1]) nodePath[i - 1].right = p.left;
else nodePath[i - 1].left = p.left;
}
}
} else {
boolean color;
Entry r = p.right;
if (r.pred()) {
r.left = p.left;
r.pred(p.pred());
if (!r.pred()) r.prev().right = r;
if (i == 0) tree = r;
else {
if (dirPath[i - 1]) nodePath[i - 1].right = r;
else nodePath[i - 1].left = r;
}
color = r.black();
r.black(p.black());
p.black(color);
dirPath[i] = true;
nodePath[i++] = r;
} else {
Entry s;
int j = i++;
while (true) {
dirPath[i] = false;
nodePath[i++] = r;
s = r.left;
if (s.pred()) break;
r = s;
}
dirPath[j] = true;
nodePath[j] = s;
if (s.succ()) r.pred(s);
else r.left = s.right;
s.left = p.left;
if (!p.pred()) {
p.prev().right = s;
s.pred(false);
}
s.right(p.right);
color = s.black();
s.black(p.black());
p.black(color);
if (j == 0) tree = s;
else {
if (dirPath[j - 1]) nodePath[j - 1].right = s;
else nodePath[j - 1].left = s;
}
}
}
int maxDepth = i;
if (p.black()) {
for (; i > 0; i--) {
if (dirPath[i - 1] && !nodePath[i - 1].succ() || !dirPath[i - 1] && !nodePath[i - 1].pred()) {
Entry x = dirPath[i - 1] ? nodePath[i - 1].right : nodePath[i - 1].left;
if (!x.black()) {
x.black(true);
break;
}
}
if (!dirPath[i - 1]) {
Entry w = nodePath[i - 1].right;
if (!w.black()) {
w.black(true);
nodePath[i - 1].black(false);
nodePath[i - 1].right = w.left;
w.left = nodePath[i - 1];
if (i < 2) tree = w;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = w;
else nodePath[i - 2].left = w;
}
nodePath[i] = nodePath[i - 1];
dirPath[i] = false;
nodePath[i - 1] = w;
if (maxDepth == i++) maxDepth++;
w = nodePath[i - 1].right;
}
if ((w.pred() || w.left.black()) && (w.succ() || w.right.black())) {
w.black(false);
} else {
if (w.succ() || w.right.black()) {
Entry y = w.left;
y.black(true);
w.black(false);
w.left = y.right;
y.right = w;
w = nodePath[i - 1].right = y;
if (w.succ()) {
w.succ(false);
w.right.pred(w);
}
}
w.black(nodePath[i - 1].black());
nodePath[i - 1].black(true);
w.right.black(true);
nodePath[i - 1].right = w.left;
w.left = nodePath[i - 1];
if (i < 2) tree = w;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = w;
else nodePath[i - 2].left = w;
}
if (w.pred()) {
w.pred(false);
nodePath[i - 1].succ(w);
}
break;
}
} else {
Entry w = nodePath[i - 1].left;
if (!w.black()) {
w.black(true);
nodePath[i - 1].black(false);
nodePath[i - 1].left = w.right;
w.right = nodePath[i - 1];
if (i < 2) tree = w;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = w;
else nodePath[i - 2].left = w;
}
nodePath[i] = nodePath[i - 1];
dirPath[i] = true;
nodePath[i - 1] = w;
if (maxDepth == i++) maxDepth++;
w = nodePath[i - 1].left;
}
if ((w.pred() || w.left.black()) && (w.succ() || w.right.black())) {
w.black(false);
} else {
if (w.pred() || w.left.black()) {
Entry y = w.right;
y.black(true);
w.black(false);
w.right = y.left;
y.left = w;
w = nodePath[i - 1].left = y;
if (w.pred()) {
w.pred(false);
w.left.succ(w);
}
}
w.black(nodePath[i - 1].black());
nodePath[i - 1].black(true);
w.left.black(true);
nodePath[i - 1].left = w.right;
w.right = nodePath[i - 1];
if (i < 2) tree = w;
else {
if (dirPath[i - 2]) nodePath[i - 2].right = w;
else nodePath[i - 2].left = w;
}
if (w.succ()) {
w.succ(false);
nodePath[i - 1].pred(w);
}
break;
}
}
}
if (tree != null) tree.black(true);
}
modified = true;
count--;
// We clean up the node path, or we could have stale references later.
while (maxDepth-- != 0) nodePath[maxDepth] = null;
return p.value;
}
@Override
public boolean containsValue(final int v) {
final ValueIterator i = new ValueIterator();
int ev;
int j = count;
while (j-- != 0) {
ev = i.nextInt();
if (((ev) == (v))) return true;
}
return false;
}
@Override
public void clear() {
count = 0;
tree = null;
entries = null;
values = null;
keys = null;
firstEntry = lastEntry = null;
}
/**
* This class represent an entry in a tree map.
*
*
* We use the only "metadata", i.e., {@link Entry#info}, to store information about color,
* predecessor status and successor status.
*
*
* Note that since the class is recursive, it can be considered equivalently a tree.
*/
private static final class Entry extends AbstractInt2IntMap.BasicEntry implements Cloneable {
/** The the bit in this mask is true, the node is black. */
private static final int BLACK_MASK = 1;
/** If the bit in this mask is true, {@link #right} points to a successor. */
private static final int SUCC_MASK = 1 << 31;
/** If the bit in this mask is true, {@link #left} points to a predecessor. */
private static final int PRED_MASK = 1 << 30;
/** The pointers to the left and right subtrees. */
Entry left, right;
/**
* This integers holds different information in different bits (see {@link #SUCC_MASK} and
* {@link #PRED_MASK}.
*/
int info;
Entry() {
super((0), (0));
}
/**
* Creates a new entry with the given key and value.
*
* @param k a key.
* @param v a value.
*/
Entry(final int k, final int v) {
super(k, v);
info = SUCC_MASK | PRED_MASK;
}
/**
* Returns the left subtree.
*
* @return the left subtree ({@code null} if the left subtree is empty).
*/
Entry left() {
return (info & PRED_MASK) != 0 ? null : left;
}
/**
* Returns the right subtree.
*
* @return the right subtree ({@code null} if the right subtree is empty).
*/
Entry right() {
return (info & SUCC_MASK) != 0 ? null : right;
}
/**
* Checks whether the left pointer is really a predecessor.
*
* @return true if the left pointer is a predecessor.
*/
boolean pred() {
return (info & PRED_MASK) != 0;
}
/**
* Checks whether the right pointer is really a successor.
*
* @return true if the right pointer is a successor.
*/
boolean succ() {
return (info & SUCC_MASK) != 0;
}
/**
* Sets whether the left pointer is really a predecessor.
*
* @param pred if true then the left pointer will be considered a predecessor.
*/
void pred(final boolean pred) {
if (pred) info |= PRED_MASK;
else info &= ~PRED_MASK;
}
/**
* Sets whether the right pointer is really a successor.
*
* @param succ if true then the right pointer will be considered a successor.
*/
void succ(final boolean succ) {
if (succ) info |= SUCC_MASK;
else info &= ~SUCC_MASK;
}
/**
* Sets the left pointer to a predecessor.
*
* @param pred the predecessr.
*/
void pred(final Entry pred) {
info |= PRED_MASK;
left = pred;
}
/**
* Sets the right pointer to a successor.
*
* @param succ the successor.
*/
void succ(final Entry succ) {
info |= SUCC_MASK;
right = succ;
}
/**
* Sets the left pointer to the given subtree.
*
* @param left the new left subtree.
*/
void left(final Entry left) {
info &= ~PRED_MASK;
this.left = left;
}
/**
* Sets the right pointer to the given subtree.
*
* @param right the new right subtree.
*/
void right(final Entry right) {
info &= ~SUCC_MASK;
this.right = right;
}
/**
* Returns whether this node is black.
*
* @return true iff this node is black.
*/
boolean black() {
return (info & BLACK_MASK) != 0;
}
/**
* Sets whether this node is black.
*
* @param black if true, then this node becomes black; otherwise, it becomes red..
*/
void black(final boolean black) {
if (black) info |= BLACK_MASK;
else info &= ~BLACK_MASK;
}
/**
* Computes the next entry in the set order.
*
* @return the next entry ({@code null}) if this is the last entry).
*/
Entry next() {
Entry next = this.right;
if ((info & SUCC_MASK) == 0) while ((next.info & PRED_MASK) == 0) next = next.left;
return next;
}
/**
* Computes the previous entry in the set order.
*
* @return the previous entry ({@code null}) if this is the first entry).
*/
Entry prev() {
Entry prev = this.left;
if ((info & PRED_MASK) == 0) while ((prev.info & SUCC_MASK) == 0) prev = prev.right;
return prev;
}
@Override
public int setValue(final int value) {
final int oldValue = this.value;
this.value = value;
return oldValue;
}
@Override
public Entry clone() {
Entry c;
try {
c = (Entry)super.clone();
} catch (CloneNotSupportedException cantHappen) {
throw new InternalError();
}
c.key = key;
c.value = value;
c.info = info;
return c;
}
@Override
@SuppressWarnings("unchecked")
public boolean equals(final Object o) {
if (!(o instanceof Map.Entry)) return false;
Map.Entry e = (Map.Entry)o;
return ((key) == ((e.getKey()).intValue())) && ((value) == ((e.getValue()).intValue()));
}
@Override
public int hashCode() {
return (key) ^ (value);
}
@Override
public String toString() {
return key + "=>" + value;
}
/*
public void prettyPrint() {
prettyPrint(0);
}
public void prettyPrint(int level) {
if (pred()) {
for (int i = 0; i < level; i++)
System.err.print(" ");
System.err.println("pred: " + left);
}
else if (left != null)
left.prettyPrint(level +1);
for (int i = 0; i < level; i++)
System.err.print(" ");
System.err.println(key + "=" + value + " (" + balance() + ")");
if (succ()) {
for (int i = 0; i < level; i++)
System.err.print(" ");
System.err.println("succ: " + right);
}
else if (right != null)
right.prettyPrint(level + 1);
}*/
}
/*
public void prettyPrint() {
System.err.println("size: " + count);
if (tree != null) tree.prettyPrint();
}*/
@Override
public boolean containsKey(final int k) {
return findKey(k) != null;
}
@Override
public int size() {
return count;
}
@Override
public boolean isEmpty() {
return count == 0;
}
@Override
public int get(final int k) {
final Entry e = findKey(k);
return e == null ? defRetValue : e.value;
}
@Override
public int firstIntKey() {
if (tree == null) throw new NoSuchElementException();
return firstEntry.key;
}
@Override
public int lastIntKey() {
if (tree == null) throw new NoSuchElementException();
return lastEntry.key;
}
/**
* An abstract iterator on the whole range.
*
*
* This class can iterate in both directions on a threaded tree.
*/
private class TreeIterator {
/**
* The entry that will be returned by the next call to {@link java.util.ListIterator#previous()} (or
* {@code null} if no previous entry exists).
*/
Entry prev;
/**
* The entry that will be returned by the next call to {@link java.util.ListIterator#next()} (or
* {@code null} if no next entry exists).
*/
Entry next;
/**
* The last entry that was returned (or {@code null} if we did not iterate or used
* {@link #remove()}).
*/
Entry curr;
/**
* The current index (in the sense of a {@link java.util.ListIterator}). Note that this value is not
* meaningful when this {@link TreeIterator} has been created using the nonempty constructor.
*/
int index = 0;
TreeIterator() {
next = firstEntry;
}
TreeIterator(final int k) {
if ((next = locateKey(k)) != null) {
if (compare(next.key, k) <= 0) {
prev = next;
next = next.next();
} else prev = next.prev();
}
}
public boolean hasNext() {
return next != null;
}
public boolean hasPrevious() {
return prev != null;
}
void updateNext() {
next = next.next();
}
Entry nextEntry() {
if (!hasNext()) throw new NoSuchElementException();
curr = prev = next;
index++;
updateNext();
return curr;
}
void updatePrevious() {
prev = prev.prev();
}
Entry previousEntry() {
if (!hasPrevious()) throw new NoSuchElementException();
curr = next = prev;
index--;
updatePrevious();
return curr;
}
public int nextIndex() {
return index;
}
public int previousIndex() {
return index - 1;
}
public void remove() {
if (curr == null) throw new IllegalStateException();
/* If the last operation was a next(), we are removing an entry that preceeds
the current index, and thus we must decrement it. */
if (curr == prev) index--;
next = prev = curr;
updatePrevious();
updateNext();
Int2IntRBTreeMap.this.remove(curr.key);
curr = null;
}
public int skip(final int n) {
int i = n;
while (i-- != 0 && hasNext()) nextEntry();
return n - i - 1;
}
public int back(final int n) {
int i = n;
while (i-- != 0 && hasPrevious()) previousEntry();
return n - i - 1;
}
}
/**
* An iterator on the whole range.
*
*
* This class can iterate in both directions on a threaded tree.
*/
private class EntryIterator extends TreeIterator implements ObjectListIterator {
EntryIterator() {
}
EntryIterator(final int k) {
super(k);
}
@Override
public Int2IntMap.Entry next() {
return nextEntry();
}
@Override
public Int2IntMap.Entry previous() {
return previousEntry();
}
}
@Override
public ObjectSortedSet int2IntEntrySet() {
if (entries == null) entries = new AbstractObjectSortedSet() {
final Comparator comparator = (Int2IntRBTreeMap.this.actualComparator == null ? (Comparator)(x, y) -> (Integer.compare((x.getIntKey()), (y.getIntKey()))) : (Comparator)(x, y) -> Int2IntRBTreeMap.this.actualComparator.compare(x.getIntKey(), y.getIntKey()));
@Override
public Comparator comparator() {
return comparator;
}
@Override
public ObjectBidirectionalIterator iterator() {
return new EntryIterator();
}
@Override
public ObjectBidirectionalIterator iterator(final Int2IntMap.Entry from) {
return new EntryIterator(from.getIntKey());
}
@Override
public boolean contains(final Object o) {
if (o == null || !(o instanceof Map.Entry)) return false;
final Map.Entry e = (Map.Entry)o;
if (e.getKey() == null) return false;
if (!(e.getKey() instanceof Integer)) return false;
if (e.getValue() == null || !(e.getValue() instanceof Integer)) return false;
final Entry f = findKey(((Integer)(e.getKey())).intValue());
return e.equals(f);
}
@Override
public boolean remove(final Object o) {
if (!(o instanceof Map.Entry)) return false;
final Map.Entry e = (Map.Entry)o;
if (e.getKey() == null) return false;
if (!(e.getKey() instanceof Integer)) return false;
if (e.getValue() == null || !(e.getValue() instanceof Integer)) return false;
final Entry f = findKey(((Integer)(e.getKey())).intValue());
if (f == null || !((f.getIntValue()) == (((Integer)(e.getValue())).intValue()))) return false;
Int2IntRBTreeMap.this.remove(f.key);
return true;
}
@Override
public int size() {
return count;
}
@Override
public void clear() {
Int2IntRBTreeMap.this.clear();
}
@Override
public Int2IntMap.Entry first() {
return firstEntry;
}
@Override
public Int2IntMap.Entry last() {
return lastEntry;
}
@Override
public ObjectSortedSet subSet(Int2IntMap.Entry from, Int2IntMap.Entry to) {
return subMap(from.getIntKey(), to.getIntKey()).int2IntEntrySet();
}
@Override
public ObjectSortedSet headSet(Int2IntMap.Entry to) {
return headMap(to.getIntKey()).int2IntEntrySet();
}
@Override
public ObjectSortedSet tailSet(Int2IntMap.Entry from) {
return tailMap(from.getIntKey()).int2IntEntrySet();
}
};
return entries;
}
/**
* An iterator on the whole range of keys.
*
*
* This class can iterate in both directions on the keys of a threaded tree. We simply override the
* {@link java.util.ListIterator#next()}/{@link java.util.ListIterator#previous()} methods (and
* possibly their type-specific counterparts) so that they return keys instead of entries.
*/
private final class KeyIterator extends TreeIterator implements IntListIterator {
public KeyIterator() {
}
public KeyIterator(final int k) {
super(k);
}
@Override
public int nextInt() {
return nextEntry().key;
}
@Override
public int previousInt() {
return previousEntry().key;
}
};
/** A keyset implementation using a more direct implementation for iterators. */
private class KeySet extends AbstractInt2IntSortedMap.KeySet {
@Override
public IntBidirectionalIterator iterator() {
return new KeyIterator();
}
@Override
public IntBidirectionalIterator iterator(final int from) {
return new KeyIterator(from);
}
}
/**
* Returns a type-specific sorted set view of the keys contained in this map.
*
*
* In addition to the semantics of {@link java.util.Map#keySet()}, you can safely cast the set
* returned by this call to a type-specific sorted set interface.
*
* @return a type-specific sorted set view of the keys contained in this map.
*/
@Override
public IntSortedSet keySet() {
if (keys == null) keys = new KeySet();
return keys;
}
/**
* An iterator on the whole range of values.
*
*
* This class can iterate in both directions on the values of a threaded tree. We simply override
* the {@link java.util.ListIterator#next()}/{@link java.util.ListIterator#previous()} methods (and
* possibly their type-specific counterparts) so that they return values instead of entries.
*/
private final class ValueIterator extends TreeIterator implements IntListIterator {
@Override
public int nextInt() {
return nextEntry().value;
}
@Override
public int previousInt() {
return previousEntry().value;
}
};
/**
* Returns a type-specific collection view of the values contained in this map.
*
*
* In addition to the semantics of {@link java.util.Map#values()}, you can safely cast the
* collection returned by this call to a type-specific collection interface.
*
* @return a type-specific collection view of the values contained in this map.
*/
@Override
public IntCollection values() {
if (values == null) values = new AbstractIntCollection() {
@Override
public IntIterator iterator() {
return new ValueIterator();
}
@Override
public boolean contains(final int k) {
return containsValue(k);
}
@Override
public int size() {
return count;
}
@Override
public void clear() {
Int2IntRBTreeMap.this.clear();
}
};
return values;
}
@Override
public IntComparator comparator() {
return actualComparator;
}
@Override
public Int2IntSortedMap headMap(int to) {
return new Submap((0), true, to, false);
}
@Override
public Int2IntSortedMap tailMap(int from) {
return new Submap(from, false, (0), true);
}
@Override
public Int2IntSortedMap subMap(int from, int to) {
return new Submap(from, false, to, false);
}
/**
* A submap with given range.
*
*
* This class represents a submap. One has to specify the left/right limits (which can be set to
* -∞ or ∞). Since the submap is a view on the map, at a given moment it could happen
* that the limits of the range are not any longer in the main map. Thus, things such as
* {@link java.util.SortedMap#firstKey()} or {@link java.util.Collection#size()} must be always
* computed on-the-fly.
*/
private final class Submap extends AbstractInt2IntSortedMap implements java.io.Serializable {
private static final long serialVersionUID = -7046029254386353129L;
/** The start of the submap range, unless {@link #bottom} is true. */
int from;
/** The end of the submap range, unless {@link #top} is true. */
int to;
/** If true, the submap range starts from -∞. */
boolean bottom;
/** If true, the submap range goes to ∞. */
boolean top;
/** Cached set of entries. */
protected transient ObjectSortedSet entries;
/** Cached set of keys. */
protected transient IntSortedSet keys;
/** Cached collection of values. */
protected transient IntCollection values;
/**
* Creates a new submap with given key range.
*
* @param from the start of the submap range.
* @param bottom if true, the first parameter is ignored and the range starts from -∞.
* @param to the end of the submap range.
* @param top if true, the third parameter is ignored and the range goes to ∞.
*/
public Submap(final int from, final boolean bottom, final int to, final boolean top) {
if (!bottom && !top && Int2IntRBTreeMap.this.compare(from, to) > 0) throw new IllegalArgumentException("Start key (" + from + ") is larger than end key (" + to + ")");
this.from = from;
this.bottom = bottom;
this.to = to;
this.top = top;
this.defRetValue = Int2IntRBTreeMap.this.defRetValue;
}
@Override
public void clear() {
final SubmapIterator i = new SubmapIterator();
while (i.hasNext()) {
i.nextEntry();
i.remove();
}
}
/**
* Checks whether a key is in the submap range.
*
* @param k a key.
* @return true if is the key is in the submap range.
*/
final boolean in(final int k) {
return (bottom || Int2IntRBTreeMap.this.compare(k, from) >= 0) && (top || Int2IntRBTreeMap.this.compare(k, to) < 0);
}
@Override
public ObjectSortedSet int2IntEntrySet() {
if (entries == null) entries = new AbstractObjectSortedSet() {
@Override
public ObjectBidirectionalIterator iterator() {
return new SubmapEntryIterator();
}
@Override
public ObjectBidirectionalIterator iterator(final Int2IntMap.Entry from) {
return new SubmapEntryIterator(from.getIntKey());
}
@Override
public Comparator comparator() {
return Int2IntRBTreeMap.this.int2IntEntrySet().comparator();
}
@Override
public boolean contains(final Object o) {
if (!(o instanceof Map.Entry)) return false;
final Map.Entry e = (Map.Entry)o;
if (e.getKey() == null || !(e.getKey() instanceof Integer)) return false;
if (e.getValue() == null || !(e.getValue() instanceof Integer)) return false;
final Int2IntRBTreeMap.Entry f = findKey(((Integer)(e.getKey())).intValue());
return f != null && in(f.key) && e.equals(f);
}
@Override
public boolean remove(final Object o) {
if (!(o instanceof Map.Entry)) return false;
final Map.Entry e = (Map.Entry)o;
if (e.getKey() == null || !(e.getKey() instanceof Integer)) return false;
if (e.getValue() == null || !(e.getValue() instanceof Integer)) return false;
final Int2IntRBTreeMap.Entry f = findKey(((Integer)(e.getKey())).intValue());
if (f != null && in(f.key)) Submap.this.remove(f.key);
return f != null;
}
@Override
public int size() {
int c = 0;
for (Iterator i = iterator(); i.hasNext(); i.next()) c++;
return c;
}
@Override
public boolean isEmpty() {
return !new SubmapIterator().hasNext();
}
@Override
public void clear() {
Submap.this.clear();
}
@Override
public Int2IntMap.Entry first() {
return firstEntry();
}
@Override
public Int2IntMap.Entry last() {
return lastEntry();
}
@Override
public ObjectSortedSet subSet(Int2IntMap.Entry from, Int2IntMap.Entry to) {
return subMap(from.getIntKey(), to.getIntKey()).int2IntEntrySet();
}
@Override
public ObjectSortedSet headSet(Int2IntMap.Entry to) {
return headMap(to.getIntKey()).int2IntEntrySet();
}
@Override
public ObjectSortedSet tailSet(Int2IntMap.Entry from) {
return tailMap(from.getIntKey()).int2IntEntrySet();
}
};
return entries;
}
private class KeySet extends AbstractInt2IntSortedMap.KeySet {
@Override
public IntBidirectionalIterator iterator() {
return new SubmapKeyIterator();
}
@Override
public IntBidirectionalIterator iterator(final int from) {
return new SubmapKeyIterator(from);
}
}
@Override
public IntSortedSet keySet() {
if (keys == null) keys = new KeySet();
return keys;
}
@Override
public IntCollection values() {
if (values == null) values = new AbstractIntCollection() {
@Override
public IntIterator iterator() {
return new SubmapValueIterator();
}
@Override
public boolean contains(final int k) {
return containsValue(k);
}
@Override
public int size() {
return Submap.this.size();
}
@Override
public void clear() {
Submap.this.clear();
}
};
return values;
}
@Override
public boolean containsKey(final int k) {
return in(k) && Int2IntRBTreeMap.this.containsKey(k);
}
@Override
public boolean containsValue(final int v) {
final SubmapIterator i = new SubmapIterator();
int ev;
while (i.hasNext()) {
ev = i.nextEntry().value;
if (((ev) == (v))) return true;
}
return false;
}
@Override
public int get(final int k) {
final Int2IntRBTreeMap.Entry e;
final int kk = k;
return in(kk) && (e = findKey(kk)) != null ? e.value : this.defRetValue;
}
@Override
public int put(final int k, final int v) {
modified = false;
if (!in(k)) throw new IllegalArgumentException("Key (" + k + ") out of range [" + (bottom ? "-" : String.valueOf(from)) + ", " + (top ? "-" : String.valueOf(to)) + ")");
final int oldValue = Int2IntRBTreeMap.this.put(k, v);
return modified ? this.defRetValue : oldValue;
}
@Override
public int remove(final int k) {
modified = false;
if (!in(k)) return this.defRetValue;
final int oldValue = Int2IntRBTreeMap.this.remove(k);
return modified ? oldValue : this.defRetValue;
}
@Override
public int size() {
final SubmapIterator i = new SubmapIterator();
int n = 0;
while (i.hasNext()) {
n++;
i.nextEntry();
}
return n;
}
@Override
public boolean isEmpty() {
return !new SubmapIterator().hasNext();
}
@Override
public IntComparator comparator() {
return actualComparator;
}
@Override
public Int2IntSortedMap headMap(final int to) {
if (top) return new Submap(from, bottom, to, false);
return compare(to, this.to) < 0 ? new Submap(from, bottom, to, false) : this;
}
@Override
public Int2IntSortedMap tailMap(final int from) {
if (bottom) return new Submap(from, false, to, top);
return compare(from, this.from) > 0 ? new Submap(from, false, to, top) : this;
}
@Override
public Int2IntSortedMap subMap(int from, int to) {
if (top && bottom) return new Submap(from, false, to, false);
if (!top) to = compare(to, this.to) < 0 ? to : this.to;
if (!bottom) from = compare(from, this.from) > 0 ? from : this.from;
if (!top && !bottom && from == this.from && to == this.to) return this;
return new Submap(from, false, to, false);
}
/**
* Locates the first entry.
*
* @return the first entry of this submap, or {@code null} if the submap is empty.
*/
public Int2IntRBTreeMap.Entry firstEntry() {
if (tree == null) return null;
// If this submap goes to -infinity, we return the main map first entry; otherwise, we locate the
// start of the map.
Int2IntRBTreeMap.Entry e;
if (bottom) e = firstEntry;
else {
e = locateKey(from);
// If we find either the start or something greater we're OK.
if (compare(e.key, from) < 0) e = e.next();
}
// Finally, if this submap doesn't go to infinity, we check that the resulting key isn't greater
// than the end.
if (e == null || !top && compare(e.key, to) >= 0) return null;
return e;
}
/**
* Locates the last entry.
*
* @return the last entry of this submap, or {@code null} if the submap is empty.
*/
public Int2IntRBTreeMap.Entry lastEntry() {
if (tree == null) return null;
// If this submap goes to infinity, we return the main map last entry; otherwise, we locate the end
// of the map.
Int2IntRBTreeMap.Entry e;
if (top) e = lastEntry;
else {
e = locateKey(to);
// If we find something smaller than the end we're OK.
if (compare(e.key, to) >= 0) e = e.prev();
}
// Finally, if this submap doesn't go to -infinity, we check that the resulting key isn't smaller
// than the start.
if (e == null || !bottom && compare(e.key, from) < 0) return null;
return e;
}
@Override
public int firstIntKey() {
Int2IntRBTreeMap.Entry e = firstEntry();
if (e == null) throw new NoSuchElementException();
return e.key;
}
@Override
public int lastIntKey() {
Int2IntRBTreeMap.Entry e = lastEntry();
if (e == null) throw new NoSuchElementException();
return e.key;
}
/**
* An iterator for subranges.
*
*
* This class inherits from {@link TreeIterator}, but overrides the methods that update the pointer
* after a {@link java.util.ListIterator#next()} or {@link java.util.ListIterator#previous()}. If we
* would move out of the range of the submap we just overwrite the next or previous entry with
* {@code null}.
*/
private class SubmapIterator extends TreeIterator {
SubmapIterator() {
next = firstEntry();
}
SubmapIterator(final int k) {
this();
if (next != null) {
if (!bottom && compare(k, next.key) < 0) prev = null;
else if (!top && compare(k, (prev = lastEntry()).key) >= 0) next = null;
else {
next = locateKey(k);
if (compare(next.key, k) <= 0) {
prev = next;
next = next.next();
} else prev = next.prev();
}
}
}
@Override
void updatePrevious() {
prev = prev.prev();
if (!bottom && prev != null && Int2IntRBTreeMap.this.compare(prev.key, from) < 0) prev = null;
}
@Override
void updateNext() {
next = next.next();
if (!top && next != null && Int2IntRBTreeMap.this.compare(next.key, to) >= 0) next = null;
}
}
private class SubmapEntryIterator extends SubmapIterator implements ObjectListIterator {
SubmapEntryIterator() {
}
SubmapEntryIterator(final int k) {
super(k);
}
@Override
public Int2IntMap.Entry next() {
return nextEntry();
}
@Override
public Int2IntMap.Entry previous() {
return previousEntry();
}
}
/**
* An iterator on a subrange of keys.
*
*
* This class can iterate in both directions on a subrange of the keys of a threaded tree. We simply
* override the {@link java.util.ListIterator#next()}/{@link java.util.ListIterator#previous()}
* methods (and possibly their type-specific counterparts) so that they return keys instead of
* entries.
*/
private final class SubmapKeyIterator extends SubmapIterator implements IntListIterator {
public SubmapKeyIterator() {
super();
}
public SubmapKeyIterator(int from) {
super(from);
}
@Override
public int nextInt() {
return nextEntry().key;
}
@Override
public int previousInt() {
return previousEntry().key;
}
};
/**
* An iterator on a subrange of values.
*
*
* This class can iterate in both directions on the values of a subrange of the keys of a threaded
* tree. We simply override the
* {@link java.util.ListIterator#next()}/{@link java.util.ListIterator#previous()} methods (and
* possibly their type-specific counterparts) so that they return values instead of entries.
*/
private final class SubmapValueIterator extends SubmapIterator implements IntListIterator {
@Override
public int nextInt() {
return nextEntry().value;
}
@Override
public int previousInt() {
return previousEntry().value;
}
};
}
/**
* Returns a deep copy of this tree map.
*
*
* This method performs a deep copy of this tree map; the data stored in the set, however, is not
* cloned. Note that this makes a difference only for object keys.
*
* @return a deep copy of this tree map.
*/
@Override
public Int2IntRBTreeMap clone() {
Int2IntRBTreeMap c;
try {
c = (Int2IntRBTreeMap)super.clone();
} catch (CloneNotSupportedException cantHappen) {
throw new InternalError();
}
c.keys = null;
c.values = null;
c.entries = null;
c.allocatePaths();
if (count != 0) {
// Also this apparently unfathomable code is derived from GNU libavl.
Entry e, p, q, rp = new Entry(), rq = new Entry();
p = rp;
rp.left(tree);
q = rq;
rq.pred(null);
while (true) {
if (!p.pred()) {
e = p.left.clone();
e.pred(q.left);
e.succ(q);
q.left(e);
p = p.left;
q = q.left;
} else {
while (p.succ()) {
p = p.right;
if (p == null) {
q.right = null;
c.tree = rq.left;
c.firstEntry = c.tree;
while (c.firstEntry.left != null) c.firstEntry = c.firstEntry.left;
c.lastEntry = c.tree;
while (c.lastEntry.right != null) c.lastEntry = c.lastEntry.right;
return c;
}
q = q.right;
}
p = p.right;
q = q.right;
}
if (!p.succ()) {
e = p.right.clone();
e.succ(q.right);
e.pred(q);
q.right(e);
}
}
}
return c;
}
private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
int n = count;
EntryIterator i = new EntryIterator();
Entry e;
s.defaultWriteObject();
while (n-- != 0) {
e = i.nextEntry();
s.writeInt(e.key);
s.writeInt(e.value);
}
}
/**
* Reads the given number of entries from the input stream, returning the corresponding tree.
*
* @param s the input stream.
* @param n the (positive) number of entries to read.
* @param pred the entry containing the key that preceeds the first key in the tree.
* @param succ the entry containing the key that follows the last key in the tree.
*/
private Entry readTree(final java.io.ObjectInputStream s, final int n, final Entry pred, final Entry succ) throws java.io.IOException, ClassNotFoundException {
if (n == 1) {
final Entry top = new Entry(s.readInt(), s.readInt());
top.pred(pred);
top.succ(succ);
top.black(true);
return top;
}
if (n == 2) {
/* We handle separately this case so that recursion will
*always* be on nonempty subtrees. */
final Entry top = new Entry(s.readInt(), s.readInt());
top.black(true);
top.right(new Entry(s.readInt(), s.readInt()));
top.right.pred(top);
top.pred(pred);
top.right.succ(succ);
return top;
}
// The right subtree is the largest one.
final int rightN = n / 2, leftN = n - rightN - 1;
final Entry top = new Entry();
top.left(readTree(s, leftN, pred, top));
top.key = s.readInt();
top.value = s.readInt();
top.black(true);
top.right(readTree(s, rightN, top, succ));
if (n + 2 == ((n + 2) & -(n + 2))) top.right.black(false); // Quick test for determining whether n + 2 is a
// power of 2.
return top;
}
private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
s.defaultReadObject();
/* The storedComparator is now correctly set, but we must restore
on-the-fly the actualComparator. */
setActualComparator();
allocatePaths();
if (count != 0) {
tree = readTree(s, count, null, null);
Entry e;
e = tree;
while (e.left() != null) e = e.left();
firstEntry = e;
e = tree;
while (e.right() != null) e = e.right();
lastEntry = e;
}
}
}