http://fastutil.di.unimi.it/: 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.
  • Sebastiano Vigna 
/*
	* Copyright (C) 2002-2019 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.longs;
import it.unimi.dsi.fastutil.Hash;
import it.unimi.dsi.fastutil.HashCommon;
import static it.unimi.dsi.fastutil.HashCommon.arraySize;
import static it.unimi.dsi.fastutil.HashCommon.maxFill;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.NoSuchElementException;

A type-specific linked hash set with with a fast, small-footprint
implementation.


Instances of this class use a hash table to represent a set. The table is
filled up to a specified load factor, and then doubled in size to
accommodate new entries. If the table is emptied below one fourth of
the load factor, it is halved in size; however, the table is never reduced to
a size smaller than that at creation time: this approach makes it possible to
create sets with a large capacity in which insertions and deletions do not
cause immediately rehashing. Moreover, halving is not performed when deleting
entries from an iterator, as it would interfere with the iteration process.

 Note that clear() does not modify the hash table size. Rather, a family of trimming methods lets you control the size of the table; this is particularly useful if you reuse instances of this class. 

Iterators generated by this set will enumerate elements in the same order in
which they have been added to the set (addition of elements already present
in the set does not change the iteration order). Note that this order has
nothing in common with the natural order of the keys. The order is kept by
means of a doubly linked list, represented via an array of longs
parallel to the table.

 This class implements the interface of a sorted set, so to allow easy access of the iteration order: for instance, you can get the first element in iteration order with first() without having to create an iterator; however, this class partially violates the SortedSet contract because all subset methods throw an exception and comparator() returns always null. 
 Additional methods, such as addAndMoveToFirst(), make it easy to use instances of this class as a cache (e.g., with LRU policy). 
 The iterators provided by this class are type-specific list iterators, and can be started at any element which is in the set (if the provided element is not in the set, a NoSuchElementException exception will be thrown). If, however, the provided element is not the first or last element in the set, the first access to the list index will require linear time, as in the worst case the entire set must be scanned in iteration order to retrieve the positional index of the starting element. If you use just the methods of a type-specific BidirectionalIterator, however, all operations will be performed in constant time. 
See Also:
/**
 * A type-specific linked hash set with with a fast, small-footprint
 * implementation.
 *
 * <p>
 * Instances of this class use a hash table to represent a set. The table is
 * filled up to a specified <em>load factor</em>, and then doubled in size to
 * accommodate new entries. If the table is emptied below <em>one fourth</em> of
 * the load factor, it is halved in size; however, the table is never reduced to
 * a size smaller than that at creation time: this approach makes it possible to
 * create sets with a large capacity in which insertions and deletions do not
 * cause immediately rehashing. Moreover, halving is not performed when deleting
 * entries from an iterator, as it would interfere with the iteration process.
 *
 * <p>
 * Note that {@link #clear()} does not modify the hash table size. Rather, a
 * family of {@linkplain #trim() trimming methods} lets you control the size of
 * the table; this is particularly useful if you reuse instances of this class.
 *
 * <p>
 * Iterators generated by this set will enumerate elements in the same order in
 * which they have been added to the set (addition of elements already present
 * in the set does not change the iteration order). Note that this order has
 * nothing in common with the natural order of the keys. The order is kept by
 * means of a doubly linked list, represented <i>via</i> an array of longs
 * parallel to the table.
 *
 * <p>
 * This class implements the interface of a sorted set, so to allow easy access
 * of the iteration order: for instance, you can get the first element in
 * iteration order with {@code first()} without having to create an iterator;
 * however, this class partially violates the {@link java.util.SortedSet}
 * contract because all subset methods throw an exception and
 * {@link #comparator()} returns always {@code null}.
 *
 * <p>
 * Additional methods, such as {@code addAndMoveToFirst()}, make it easy to use
 * instances of this class as a cache (e.g., with LRU policy).
 *
 * <p>
 * The iterators provided by this class are type-specific
 * {@linkplain java.util.ListIterator list iterators}, and can be started at any
 * element <em>which is in the set</em> (if the provided element is not in the
 * set, a {@link NoSuchElementException} exception will be thrown). If, however,
 * the provided element is not the first or last element in the set, the first
 * access to the list index will require linear time, as in the worst case the
 * entire set must be scanned in iteration order to retrieve the positional
 * index of the starting element. If you use just the methods of a type-specific
 * {@link it.unimi.dsi.fastutil.BidirectionalIterator}, however, all operations
 * will be performed in constant time.
 *
 * @see Hash
 * @see HashCommon
 */
public class LongLinkedOpenCustomHashSet extends AbstractLongSortedSet
		implements
			java.io.Serializable,
			Cloneable,
			Hash {
	private static final long serialVersionUID = 0L;
	private static final boolean ASSERTS = false;
	
The array of keys. 
/** The array of keys. */
	protected transient long[] key;
	
The mask for wrapping a position counter. 
/** The mask for wrapping a position counter. */
	protected transient int mask;
	
Whether this set contains the null key. 
/** Whether this set contains the null key. */
	protected transient boolean containsNull;
	
The hash strategy of this custom set. 
/** The hash strategy of this custom set. */
	protected it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy;
	
The index of the first entry in iteration order. It is valid iff size is nonzero; otherwise, it contains -1. 
/**
	 * The index of the first entry in iteration order. It is valid iff
	 * {@link #size} is nonzero; otherwise, it contains -1.
	 */
	protected transient int first = -1;
	
The index of the last entry in iteration order. It is valid iff size is nonzero; otherwise, it contains -1. 
/**
	 * The index of the last entry in iteration order. It is valid iff {@link #size}
	 * is nonzero; otherwise, it contains -1.
	 */
	protected transient int last = -1;
	
For each entry, the next and the previous entry in iteration order, stored as ((prev & 0xFFFFFFFFL) << 32) | (next & 0xFFFFFFFFL). The first entry contains predecessor -1, and the last entry contains successor -1. 
/**
	 * For each entry, the next and the previous entry in iteration order, stored as
	 * {@code ((prev & 0xFFFFFFFFL) << 32) | (next & 0xFFFFFFFFL)}. The first entry
	 * contains predecessor -1, and the last entry contains successor -1.
	 */
	protected transient long[] link;
	
The current table size. Note that an additional element is allocated for
storing the null key.

/**
	 * The current table size. Note that an additional element is allocated for
	 * storing the null key.
	 */
	protected transient int n;
	
Threshold after which we rehash. It must be the table size times f. 
/**
	 * Threshold after which we rehash. It must be the table size times {@link #f}.
	 */
	protected transient int maxFill;
	
We never resize below this threshold, which is the construction-time {#n}.

/**
	 * We never resize below this threshold, which is the construction-time {#n}.
	 */
	protected final transient int minN;
	
Number of entries in the set (including the null key, if present). 
/** Number of entries in the set (including the null key, if present). */
	protected int size;
	
The acceptable load factor. 
/** The acceptable load factor. */
	protected final float f;
	
Creates a new hash set.

 The actual table size will be the least power of two greater than expected/f. 
Params:
  • expected – 
           the expected number of elements in the hash set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set.
	 *
	 * <p>
	 * The actual table size will be the least power of two greater than
	 * {@code expected}/{@code f}.
	 *
	 * @param expected
	 *            the expected number of elements in the hash set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */

	public LongLinkedOpenCustomHashSet(final int expected, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this.strategy = strategy;
		if (f <= 0 || f > 1)
			throw new IllegalArgumentException("Load factor must be greater than 0 and smaller than or equal to 1");
		if (expected < 0)
			throw new IllegalArgumentException("The expected number of elements must be nonnegative");
		this.f = f;
		minN = n = arraySize(expected, f);
		mask = n - 1;
		maxFill = maxFill(n, f);
		key = new long[n + 1];
		link = new long[n + 1];
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor. 
Params:
  • expected – 
           the expected number of elements in the hash set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor.
	 *
	 * @param expected
	 *            the expected number of elements in the hash set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final int expected,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(expected, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set with initial expected Hash.DEFAULT_INITIAL_SIZE elements and Hash.DEFAULT_LOAD_FACTOR as load factor. 
Params:
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with initial expected
	 * {@link Hash#DEFAULT_INITIAL_SIZE} elements and
	 * {@link Hash#DEFAULT_LOAD_FACTOR} as load factor.
	 * 
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(DEFAULT_INITIAL_SIZE, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set copying a given collection.

Params:
  • c –  a Collection to be copied into the new hash set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set copying a given collection.
	 *
	 * @param c
	 *            a {@link Collection} to be copied into the new hash set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final Collection<? extends Long> c, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(c.size(), f, strategy);
		addAll(c);
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given collection. 
Params:
  • c –  a Collection to be copied into the new hash set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * copying a given collection.
	 *
	 * @param c
	 *            a {@link Collection} to be copied into the new hash set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final Collection<? extends Long> c,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(c, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set copying a given type-specific collection.

Params:
  • c – 
           a type-specific collection to be copied into the new hash set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set copying a given type-specific collection.
	 *
	 * @param c
	 *            a type-specific collection to be copied into the new hash set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final LongCollection c, final float f,
			it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(c.size(), f, strategy);
		addAll(c);
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor copying a given type-specific collection. 
Params:
  • c – 
           a type-specific collection to be copied into the new hash set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * copying a given type-specific collection.
	 *
	 * @param c
	 *            a type-specific collection to be copied into the new hash set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final LongCollection c,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(c, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set using elements provided by a type-specific iterator.

Params:
  • i – 
           a type-specific iterator whose elements will fill the set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set using elements provided by a type-specific iterator.
	 *
	 * @param i
	 *            a type-specific iterator whose elements will fill the set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final LongIterator i, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(DEFAULT_INITIAL_SIZE, f, strategy);
		while (i.hasNext())
			add(i.nextLong());
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by a type-specific iterator. 
Params:
  • i – 
           a type-specific iterator whose elements will fill the set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * using elements provided by a type-specific iterator.
	 *
	 * @param i
	 *            a type-specific iterator whose elements will fill the set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final LongIterator i,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(i, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set using elements provided by an iterator.

Params:
  • i – 
           an iterator whose elements will fill the set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set using elements provided by an iterator.
	 *
	 * @param i
	 *            an iterator whose elements will fill the set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final Iterator<?> i, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(LongIterators.asLongIterator(i), f, strategy);
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor using elements provided by an iterator. 
Params:
  • i – 
           an iterator whose elements will fill the set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * using elements provided by an iterator.
	 *
	 * @param i
	 *            an iterator whose elements will fill the set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final Iterator<?> i,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(LongIterators.asLongIterator(i), strategy);
	}
	
Creates a new hash set and fills it with the elements of a given array.

Params:
  • a – 
           an array whose elements will be used to fill the set.
  • offset – 
           the first element to use.
  • length – 
           the number of elements to use.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set and fills it with the elements of a given array.
	 *
	 * @param a
	 *            an array whose elements will be used to fill the set.
	 * @param offset
	 *            the first element to use.
	 * @param length
	 *            the number of elements to use.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final long[] a, final int offset, final int length, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(length < 0 ? 0 : length, f, strategy);
		LongArrays.ensureOffsetLength(a, offset, length);
		for (int i = 0; i < length; i++)
			add(a[offset + i]);
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor and fills it with the elements of a given array. 
Params:
  • a – 
           an array whose elements will be used to fill the set.
  • offset – 
           the first element to use.
  • length – 
           the number of elements to use.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * and fills it with the elements of a given array.
	 *
	 * @param a
	 *            an array whose elements will be used to fill the set.
	 * @param offset
	 *            the first element to use.
	 * @param length
	 *            the number of elements to use.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final long[] a, final int offset, final int length,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(a, offset, length, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Creates a new hash set copying the elements of an array.

Params:
  • a – 
           an array to be copied into the new hash set.
  • f – 
           the load factor.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set copying the elements of an array.
	 *
	 * @param a
	 *            an array to be copied into the new hash set.
	 * @param f
	 *            the load factor.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final long[] a, final float f,
			final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(a, 0, a.length, f, strategy);
	}
	
Creates a new hash set with Hash.DEFAULT_LOAD_FACTOR as load factor copying the elements of an array. 
Params:
  • a – 
           an array to be copied into the new hash set.
  • strategy – 
           the strategy.
/**
	 * Creates a new hash set with {@link Hash#DEFAULT_LOAD_FACTOR} as load factor
	 * copying the elements of an array.
	 *
	 * @param a
	 *            an array to be copied into the new hash set.
	 * @param strategy
	 *            the strategy.
	 */
	public LongLinkedOpenCustomHashSet(final long[] a, final it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy) {
		this(a, DEFAULT_LOAD_FACTOR, strategy);
	}
	
Returns the hashing strategy.

Returns:the hashing strategy of this custom hash set.
/**
	 * Returns the hashing strategy.
	 *
	 * @return the hashing strategy of this custom hash set.
	 */
	public it.unimi.dsi.fastutil.longs.LongHash.Strategy strategy() {
		return strategy;
	}
	private int realSize() {
		return containsNull ? size - 1 : size;
	}
	private void ensureCapacity(final int capacity) {
		final int needed = arraySize(capacity, f);
		if (needed > n)
			rehash(needed);
	}
	private void tryCapacity(final long capacity) {
		final int needed = (int) Math.min(1 << 30,
				Math.max(2, HashCommon.nextPowerOfTwo((long) Math.ceil(capacity / f))));
		if (needed > n)
			rehash(needed);
	}
	@Override
	public boolean addAll(LongCollection c) {
		if (f <= .5)
			ensureCapacity(c.size()); // The resulting collection will be sized for c.size() elements
		else
			tryCapacity(size() + c.size()); // The resulting collection will be tentatively sized for size() + c.size()
											// elements
		return super.addAll(c);
	}
	@Override
	public boolean addAll(Collection<? extends Long> c) {
		// The resulting collection will be at least c.size() big
		if (f <= .5)
			ensureCapacity(c.size()); // The resulting collection will be sized for c.size() elements
		else
			tryCapacity(size() + c.size()); // The resulting collection will be tentatively sized for size() + c.size()
											// elements
		return super.addAll(c);
	}
	@Override
	public boolean add(final long k) {
		int pos;
		if ((strategy.equals((k), (0)))) {
			if (containsNull)
				return false;
			pos = n;
			containsNull = true;
			key[n] = k;
		} else {
			long curr;
			final long[] key = this.key;
			// The starting point.
			if (!((curr = key[pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask]) == (0))) {
				if ((strategy.equals((curr), (k))))
					return false;
				while (!((curr = key[pos = (pos + 1) & mask]) == (0)))
					if ((strategy.equals((curr), (k))))
						return false;
			}
			key[pos] = k;
		}
		if (size == 0) {
			first = last = pos;
			// Special case of SET_UPPER_LOWER(link[pos], -1, -1);
			link[pos] = -1L;
		} else {
			link[last] ^= ((link[last] ^ (pos & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			link[pos] = ((last & 0xFFFFFFFFL) << 32) | (-1 & 0xFFFFFFFFL);
			last = pos;
		}
		if (size++ >= maxFill)
			rehash(arraySize(size + 1, f));
		if (ASSERTS)
			checkTable();
		return true;
	}
	
Shifts left entries with the specified hash code, starting at the specified
position, and empties the resulting free entry.

Params:
  • pos – 
           a starting position.
/**
	 * Shifts left entries with the specified hash code, starting at the specified
	 * position, and empties the resulting free entry.
	 *
	 * @param pos
	 *            a starting position.
	 */
	protected final void shiftKeys(int pos) {
		// Shift entries with the same hash.
		int last, slot;
		long curr;
		final long[] key = this.key;
		for (;;) {
			pos = ((last = pos) + 1) & mask;
			for (;;) {
				if (((curr = key[pos]) == (0))) {
					key[last] = (0);
					return;
				}
				slot = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(curr))) & mask;
				if (last <= pos ? last >= slot || slot > pos : last >= slot && slot > pos)
					break;
				pos = (pos + 1) & mask;
			}
			key[last] = curr;
			fixPointers(pos, last);
		}
	}
	private boolean removeEntry(final int pos) {
		size--;
		fixPointers(pos);
		shiftKeys(pos);
		if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
			rehash(n / 2);
		return true;
	}
	private boolean removeNullEntry() {
		containsNull = false;
		key[n] = (0);
		size--;
		fixPointers(n);
		if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
			rehash(n / 2);
		return true;
	}

	@Override
	public boolean remove(final long k) {
		if ((strategy.equals((k), (0)))) {
			if (containsNull)
				return removeNullEntry();
			return false;
		}
		long curr;
		final long[] key = this.key;
		int pos;
		// The starting point.
		if (((curr = key[pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask]) == (0)))
			return false;
		if ((strategy.equals((k), (curr))))
			return removeEntry(pos);
		while (true) {
			if (((curr = key[pos = (pos + 1) & mask]) == (0)))
				return false;
			if ((strategy.equals((k), (curr))))
				return removeEntry(pos);
		}
	}

	@Override
	public boolean contains(final long k) {
		if ((strategy.equals((k), (0))))
			return containsNull;
		long curr;
		final long[] key = this.key;
		int pos;
		// The starting point.
		if (((curr = key[pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask]) == (0)))
			return false;
		if ((strategy.equals((k), (curr))))
			return true;
		while (true) {
			if (((curr = key[pos = (pos + 1) & mask]) == (0)))
				return false;
			if ((strategy.equals((k), (curr))))
				return true;
		}
	}
	
Removes the first key in iteration order.

Throws:
Returns:the first key.
/**
	 * Removes the first key in iteration order.
	 * 
	 * @return the first key.
	 * @throws NoSuchElementException
	 *             is this set is empty.
	 */
	public long removeFirstLong() {
		if (size == 0)
			throw new NoSuchElementException();
		final int pos = first;
		// Abbreviated version of fixPointers(pos)
		first = (int) link[pos];
		if (0 <= first) {
			// Special case of SET_PREV(link[first], -1)
			link[first] |= (-1 & 0xFFFFFFFFL) << 32;
		}
		final long k = key[pos];
		size--;
		if ((strategy.equals((k), (0)))) {
			containsNull = false;
			key[n] = (0);
		} else
			shiftKeys(pos);
		if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
			rehash(n / 2);
		return k;
	}
	
Removes the the last key in iteration order.

Throws:
Returns:the last key.
/**
	 * Removes the the last key in iteration order.
	 * 
	 * @return the last key.
	 * @throws NoSuchElementException
	 *             is this set is empty.
	 */
	public long removeLastLong() {
		if (size == 0)
			throw new NoSuchElementException();
		final int pos = last;
		// Abbreviated version of fixPointers(pos)
		last = (int) (link[pos] >>> 32);
		if (0 <= last) {
			// Special case of SET_NEXT(link[last], -1)
			link[last] |= -1 & 0xFFFFFFFFL;
		}
		final long k = key[pos];
		size--;
		if ((strategy.equals((k), (0)))) {
			containsNull = false;
			key[n] = (0);
		} else
			shiftKeys(pos);
		if (n > minN && size < maxFill / 4 && n > DEFAULT_INITIAL_SIZE)
			rehash(n / 2);
		return k;
	}
	private void moveIndexToFirst(final int i) {
		if (size == 1 || first == i)
			return;
		if (last == i) {
			last = (int) (link[i] >>> 32);
			// Special case of SET_NEXT(link[last], -1);
			link[last] |= -1 & 0xFFFFFFFFL;
		} else {
			final long linki = link[i];
			final int prev = (int) (linki >>> 32);
			final int next = (int) linki;
			link[prev] ^= ((link[prev] ^ (linki & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			link[next] ^= ((link[next] ^ (linki & 0xFFFFFFFF00000000L)) & 0xFFFFFFFF00000000L);
		}
		link[first] ^= ((link[first] ^ ((i & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
		link[i] = ((-1 & 0xFFFFFFFFL) << 32) | (first & 0xFFFFFFFFL);
		first = i;
	}
	private void moveIndexToLast(final int i) {
		if (size == 1 || last == i)
			return;
		if (first == i) {
			first = (int) link[i];
			// Special case of SET_PREV(link[first], -1);
			link[first] |= (-1 & 0xFFFFFFFFL) << 32;
		} else {
			final long linki = link[i];
			final int prev = (int) (linki >>> 32);
			final int next = (int) linki;
			link[prev] ^= ((link[prev] ^ (linki & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			link[next] ^= ((link[next] ^ (linki & 0xFFFFFFFF00000000L)) & 0xFFFFFFFF00000000L);
		}
		link[last] ^= ((link[last] ^ (i & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
		link[i] = ((last & 0xFFFFFFFFL) << 32) | (-1 & 0xFFFFFFFFL);
		last = i;
	}
	
Adds a key to the set; if the key is already present, it is moved to the
first position of the iteration order.

Params:
  • k – 
           the key.
Returns:true if the key was not present.
/**
	 * Adds a key to the set; if the key is already present, it is moved to the
	 * first position of the iteration order.
	 *
	 * @param k
	 *            the key.
	 * @return true if the key was not present.
	 */
	public boolean addAndMoveToFirst(final long k) {
		int pos;
		if ((strategy.equals((k), (0)))) {
			if (containsNull) {
				moveIndexToFirst(n);
				return false;
			}
			containsNull = true;
			pos = n;
		} else {
			// The starting point.
			final long key[] = this.key;
			pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask;
			// There's always an unused entry. TODO
			while (!((key[pos]) == (0))) {
				if ((strategy.equals((k), (key[pos])))) {
					moveIndexToFirst(pos);
					return false;
				}
				pos = (pos + 1) & mask;
			}
		}
		key[pos] = k;
		if (size == 0) {
			first = last = pos;
			// Special case of SET_UPPER_LOWER(link[pos], -1, -1);
			link[pos] = -1L;
		} else {
			link[first] ^= ((link[first] ^ ((pos & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
			link[pos] = ((-1 & 0xFFFFFFFFL) << 32) | (first & 0xFFFFFFFFL);
			first = pos;
		}
		if (size++ >= maxFill)
			rehash(arraySize(size, f));
		if (ASSERTS)
			checkTable();
		return true;
	}
	
Adds a key to the set; if the key is already present, it is moved to the last
position of the iteration order.

Params:
  • k – 
           the key.
Returns:true if the key was not present.
/**
	 * Adds a key to the set; if the key is already present, it is moved to the last
	 * position of the iteration order.
	 *
	 * @param k
	 *            the key.
	 * @return true if the key was not present.
	 */
	public boolean addAndMoveToLast(final long k) {
		int pos;
		if ((strategy.equals((k), (0)))) {
			if (containsNull) {
				moveIndexToLast(n);
				return false;
			}
			containsNull = true;
			pos = n;
		} else {
			// The starting point.
			final long key[] = this.key;
			pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask;
			// There's always an unused entry.
			while (!((key[pos]) == (0))) {
				if ((strategy.equals((k), (key[pos])))) {
					moveIndexToLast(pos);
					return false;
				}
				pos = (pos + 1) & mask;
			}
		}
		key[pos] = k;
		if (size == 0) {
			first = last = pos;
			// Special case of SET_UPPER_LOWER(link[pos], -1, -1);
			link[pos] = -1L;
		} else {
			link[last] ^= ((link[last] ^ (pos & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			link[pos] = ((last & 0xFFFFFFFFL) << 32) | (-1 & 0xFFFFFFFFL);
			last = pos;
		}
		if (size++ >= maxFill)
			rehash(arraySize(size, f));
		if (ASSERTS)
			checkTable();
		return true;
	}
	/*
	 * Removes all elements from this set.
	 *
	 * <p>To increase object reuse, this method does not change the table size. If
	 * you want to reduce the table size, you must use {@link #trim()}.
	 *
	 */
	@Override
	public void clear() {
		if (size == 0)
			return;
		size = 0;
		containsNull = false;
		Arrays.fill(key, (0));
		first = last = -1;
	}
	@Override
	public int size() {
		return size;
	}
	@Override
	public boolean isEmpty() {
		return size == 0;
	}
	
Modifies the link vector so that the given entry is removed. This method will complete in constant time. 
Params:
  • i – 
           the index of an entry.
/**
	 * Modifies the {@link #link} vector so that the given entry is removed. This
	 * method will complete in constant time.
	 *
	 * @param i
	 *            the index of an entry.
	 */
	protected void fixPointers(final int i) {
		if (size == 0) {
			first = last = -1;
			return;
		}
		if (first == i) {
			first = (int) link[i];
			if (0 <= first) {
				// Special case of SET_PREV(link[first], -1)
				link[first] |= (-1 & 0xFFFFFFFFL) << 32;
			}
			return;
		}
		if (last == i) {
			last = (int) (link[i] >>> 32);
			if (0 <= last) {
				// Special case of SET_NEXT(link[last], -1)
				link[last] |= -1 & 0xFFFFFFFFL;
			}
			return;
		}
		final long linki = link[i];
		final int prev = (int) (linki >>> 32);
		final int next = (int) linki;
		link[prev] ^= ((link[prev] ^ (linki & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
		link[next] ^= ((link[next] ^ (linki & 0xFFFFFFFF00000000L)) & 0xFFFFFFFF00000000L);
	}
	
Modifies the link vector for a shift from s to d. This method will complete in constant time. 
Params:
  • s – 
           the source position.
  • d – 
           the destination position.
/**
	 * Modifies the {@link #link} vector for a shift from s to d. This method will
	 * complete in constant time.
	 *
	 * @param s
	 *            the source position.
	 * @param d
	 *            the destination position.
	 */
	protected void fixPointers(int s, int d) {
		if (size == 1) {
			first = last = d;
			// Special case of SET(link[d], -1, -1)
			link[d] = -1L;
			return;
		}
		if (first == s) {
			first = d;
			link[(int) link[s]] ^= ((link[(int) link[s]] ^ ((d & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
			link[d] = link[s];
			return;
		}
		if (last == s) {
			last = d;
			link[(int) (link[s] >>> 32)] ^= ((link[(int) (link[s] >>> 32)] ^ (d & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			link[d] = link[s];
			return;
		}
		final long links = link[s];
		final int prev = (int) (links >>> 32);
		final int next = (int) links;
		link[prev] ^= ((link[prev] ^ (d & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
		link[next] ^= ((link[next] ^ ((d & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
		link[d] = links;
	}
	
Returns the first element of this set in iteration order.

Returns:the first element in iteration order.
/**
	 * Returns the first element of this set in iteration order.
	 *
	 * @return the first element in iteration order.
	 */
	@Override
	public long firstLong() {
		if (size == 0)
			throw new NoSuchElementException();
		return key[first];
	}
	
Returns the last element of this set in iteration order.

Returns:the last element in iteration order.
/**
	 * Returns the last element of this set in iteration order.
	 *
	 * @return the last element in iteration order.
	 */
	@Override
	public long lastLong() {
		if (size == 0)
			throw new NoSuchElementException();
		return key[last];
	}
	
{@inheritDoc}

 This implementation just throws an UnsupportedOperationException. 
/**
	 * {@inheritDoc}
	 * <p>
	 * This implementation just throws an {@link UnsupportedOperationException}.
	 */
	@Override
	public LongSortedSet tailSet(long from) {
		throw new UnsupportedOperationException();
	}
	
{@inheritDoc}

 This implementation just throws an UnsupportedOperationException. 
/**
	 * {@inheritDoc}
	 * <p>
	 * This implementation just throws an {@link UnsupportedOperationException}.
	 */
	@Override
	public LongSortedSet headSet(long to) {
		throw new UnsupportedOperationException();
	}
	
{@inheritDoc}

 This implementation just throws an UnsupportedOperationException. 
/**
	 * {@inheritDoc}
	 * <p>
	 * This implementation just throws an {@link UnsupportedOperationException}.
	 */
	@Override
	public LongSortedSet subSet(long from, long to) {
		throw new UnsupportedOperationException();
	}
	
{@inheritDoc}

 This implementation just returns null. 
/**
	 * {@inheritDoc}
	 * <p>
	 * This implementation just returns {@code null}.
	 */
	@Override
	public LongComparator comparator() {
		return null;
	}
	
A list iterator over a linked set.


This class provides a list iterator over a linked hash set. The constructor
runs in constant time.

/**
	 * A list iterator over a linked set.
	 *
	 * <p>
	 * This class provides a list iterator over a linked hash set. The constructor
	 * runs in constant time.
	 */
	private class SetIterator implements LongListIterator {
		
The entry that will be returned by the next call to ListIterator.previous() (or null if no previous entry exists). 
/**
		 * The entry that will be returned by the next call to
		 * {@link java.util.ListIterator#previous()} (or {@code null} if no previous
		 * entry exists).
		 */
		int prev = -1;
		
The entry that will be returned by the next call to ListIterator.next() (or null if no next entry exists). 
/**
		 * The entry that will be returned by the next call to
		 * {@link java.util.ListIterator#next()} (or {@code null} if no next entry
		 * exists).
		 */
		int next = -1;
		
The last entry that was returned (or -1 if we did not iterate or used remove()). 
/**
		 * The last entry that was returned (or -1 if we did not iterate or used
		 * {@link #remove()}).
		 */
		int curr = -1;
		
The current index (in the sense of a ListIterator). When -1, we do not know the current index. 
/**
		 * The current index (in the sense of a {@link java.util.ListIterator}). When
		 * -1, we do not know the current index.
		 */
		int index = -1;
		SetIterator() {
			next = first;
			index = 0;
		}
		SetIterator(long from) {
			if ((strategy.equals((from), (0)))) {
				if (LongLinkedOpenCustomHashSet.this.containsNull) {
					next = (int) link[n];
					prev = n;
					return;
				} else
					throw new NoSuchElementException("The key " + from + " does not belong to this set.");
			}
			if ((strategy.equals((key[last]), (from)))) {
				prev = last;
				index = size;
				return;
			}
			// The starting point.
			final long key[] = LongLinkedOpenCustomHashSet.this.key;
			int pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(from))) & mask;
			// There's always an unused entry.
			while (!((key[pos]) == (0))) {
				if ((strategy.equals((key[pos]), (from)))) {
					// Note: no valid index known.
					next = (int) link[pos];
					prev = pos;
					return;
				}
				pos = (pos + 1) & mask;
			}
			throw new NoSuchElementException("The key " + from + " does not belong to this set.");
		}
		@Override
		public boolean hasNext() {
			return next != -1;
		}
		@Override
		public boolean hasPrevious() {
			return prev != -1;
		}
		@Override
		public long nextLong() {
			if (!hasNext())
				throw new NoSuchElementException();
			curr = next;
			next = (int) link[curr];
			prev = curr;
			if (index >= 0)
				index++;
			if (ASSERTS)
				assert curr == n || !((key[curr]) == (0)) : "Position " + curr + " is not used";
			return key[curr];
		}
		@Override
		public long previousLong() {
			if (!hasPrevious())
				throw new NoSuchElementException();
			curr = prev;
			prev = (int) (link[curr] >>> 32);
			next = curr;
			if (index >= 0)
				index--;
			return key[curr];
		}
		private final void ensureIndexKnown() {
			if (index >= 0)
				return;
			if (prev == -1) {
				index = 0;
				return;
			}
			if (next == -1) {
				index = size;
				return;
			}
			int pos = first;
			index = 1;
			while (pos != prev) {
				pos = (int) link[pos];
				index++;
			}
		}
		@Override
		public int nextIndex() {
			ensureIndexKnown();
			return index;
		}
		@Override
		public int previousIndex() {
			ensureIndexKnown();
			return index - 1;
		}
		@Override
		public void remove() {
			ensureIndexKnown();
			if (curr == -1)
				throw new IllegalStateException();
			if (curr == prev) {
				/*
				 * If the last operation was a next(), we are removing an entry that preceeds
				 * the current index, and thus we must decrement it.
				 */
				index--;
				prev = (int) (link[curr] >>> 32);
			} else
				next = (int) link[curr];
			size--;
			/*
			 * Now we manually fix the pointers. Because of our knowledge of next and prev,
			 * this is going to be faster than calling fixPointers().
			 */
			if (prev == -1)
				first = next;
			else
				link[prev] ^= ((link[prev] ^ (next & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
			if (next == -1)
				last = prev;
			else
				link[next] ^= ((link[next] ^ ((prev & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
			int last, slot, pos = curr;
			curr = -1;
			if (pos == n) {
				LongLinkedOpenCustomHashSet.this.containsNull = false;
				LongLinkedOpenCustomHashSet.this.key[n] = (0);
			} else {
				long curr;
				final long[] key = LongLinkedOpenCustomHashSet.this.key;
				// We have to horribly duplicate the shiftKeys() code because we need to update
				// next/prev.
				for (;;) {
					pos = ((last = pos) + 1) & mask;
					for (;;) {
						if (((curr = key[pos]) == (0))) {
							key[last] = (0);
							return;
						}
						slot = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(curr))) & mask;
						if (last <= pos ? last >= slot || slot > pos : last >= slot && slot > pos)
							break;
						pos = (pos + 1) & mask;
					}
					key[last] = curr;
					if (next == pos)
						next = last;
					if (prev == pos)
						prev = last;
					fixPointers(pos, last);
				}
			}
		}
	}
	
Returns a type-specific list iterator on the elements in this set, starting
from a given element of the set. Please see the class documentation for
implementation details.

Params:
  • from – 
           an element to start from.
Throws:
Returns:a type-specific list iterator starting at the given element.
/**
	 * Returns a type-specific list iterator on the elements in this set, starting
	 * from a given element of the set. Please see the class documentation for
	 * implementation details.
	 *
	 * @param from
	 *            an element to start from.
	 * @return a type-specific list iterator starting at the given element.
	 * @throws IllegalArgumentException
	 *             if {@code from} does not belong to the set.
	 */
	@Override
	public LongListIterator iterator(long from) {
		return new SetIterator(from);
	}
	
Returns a type-specific list iterator on the elements in this set, starting
from the first element. Please see the class documentation for implementation
details.

Returns:a type-specific list iterator starting at the first element.
/**
	 * Returns a type-specific list iterator on the elements in this set, starting
	 * from the first element. Please see the class documentation for implementation
	 * details.
	 *
	 * @return a type-specific list iterator starting at the first element.
	 */
	@Override
	public LongListIterator iterator() {
		return new SetIterator();
	}
	
Rehashes this set, making the table as small as possible.


This method rehashes the table to the smallest size satisfying the load
factor. It can be used when the set will not be changed anymore, so to
optimize access speed and size.


If the table size is already the minimum possible, this method does nothing.

See Also:
Returns:true if there was enough memory to trim the set.
/**
	 * Rehashes this set, making the table as small as possible.
	 *
	 * <p>
	 * This method rehashes the table to the smallest size satisfying the load
	 * factor. It can be used when the set will not be changed anymore, so to
	 * optimize access speed and size.
	 *
	 * <p>
	 * If the table size is already the minimum possible, this method does nothing.
	 *
	 * @return true if there was enough memory to trim the set.
	 * @see #trim(int)
	 */
	public boolean trim() {
		return trim(size);
	}
	
Rehashes this set if the table is too large.


Let N be the smallest table size that can hold
max(n,size()) entries, still satisfying the load
factor. If the current table size is smaller than or equal to N,
this method does nothing. Otherwise, it rehashes this set in a table of size
N.

 This method is useful when reusing sets. Clearing a set leaves the table size untouched. If you are reusing a set many times, you can call this method with a typical size to avoid keeping around a very large table just because of a few large transient sets. 
Params:
  • n – 
           the threshold for the trimming.
See Also:
Returns:true if there was enough memory to trim the set.
/**
	 * Rehashes this set if the table is too large.
	 *
	 * <p>
	 * Let <var>N</var> be the smallest table size that can hold
	 * <code>max(n,{@link #size()})</code> entries, still satisfying the load
	 * factor. If the current table size is smaller than or equal to <var>N</var>,
	 * this method does nothing. Otherwise, it rehashes this set in a table of size
	 * <var>N</var>.
	 *
	 * <p>
	 * This method is useful when reusing sets. {@linkplain #clear() Clearing a set}
	 * leaves the table size untouched. If you are reusing a set many times, you can
	 * call this method with a typical size to avoid keeping around a very large
	 * table just because of a few large transient sets.
	 *
	 * @param n
	 *            the threshold for the trimming.
	 * @return true if there was enough memory to trim the set.
	 * @see #trim()
	 */
	public boolean trim(final int n) {
		final int l = HashCommon.nextPowerOfTwo((int) Math.ceil(n / f));
		if (l >= this.n || size > maxFill(l, f))
			return true;
		try {
			rehash(l);
		} catch (OutOfMemoryError cantDoIt) {
			return false;
		}
		return true;
	}
	
Rehashes the set.


This method implements the basic rehashing strategy, and may be overriden by
subclasses implementing different rehashing strategies (e.g., disk-based
rehashing). However, you should not override this method unless you
understand the internal workings of this class.

Params:
  • newN – 
           the new size
/**
	 * Rehashes the set.
	 *
	 * <p>
	 * This method implements the basic rehashing strategy, and may be overriden by
	 * subclasses implementing different rehashing strategies (e.g., disk-based
	 * rehashing). However, you should not override this method unless you
	 * understand the internal workings of this class.
	 *
	 * @param newN
	 *            the new size
	 */

	protected void rehash(final int newN) {
		final long key[] = this.key;
		final int mask = newN - 1; // Note that this is used by the hashing macro
		final long newKey[] = new long[newN + 1];
		int i = first, prev = -1, newPrev = -1, t, pos;
		final long link[] = this.link;
		final long newLink[] = new long[newN + 1];
		first = -1;
		for (int j = size; j-- != 0;) {
			if ((strategy.equals((key[i]), (0))))
				pos = newN;
			else {
				pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(key[i]))) & mask;
				while (!((newKey[pos]) == (0)))
					pos = (pos + 1) & mask;
			}
			newKey[pos] = key[i];
			if (prev != -1) {
				newLink[newPrev] ^= ((newLink[newPrev] ^ (pos & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
				newLink[pos] ^= ((newLink[pos] ^ ((newPrev & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
				newPrev = pos;
			} else {
				newPrev = first = pos;
				// Special case of SET(newLink[pos], -1, -1);
				newLink[pos] = -1L;
			}
			t = i;
			i = (int) link[i];
			prev = t;
		}
		this.link = newLink;
		this.last = newPrev;
		if (newPrev != -1)
			// Special case of SET_NEXT(newLink[newPrev], -1);
			newLink[newPrev] |= -1 & 0xFFFFFFFFL;
		n = newN;
		this.mask = mask;
		maxFill = maxFill(n, f);
		this.key = newKey;
	}
	
Returns a deep copy of this set.


This method performs a deep copy of this hash set; the data stored in the
set, however, is not cloned. Note that this makes a difference only for
object keys.

Returns:a deep copy of this set.
/**
	 * Returns a deep copy of this set.
	 *
	 * <p>
	 * This method performs a deep copy of this hash set; 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 set.
	 */
	@Override

	public LongLinkedOpenCustomHashSet clone() {
		LongLinkedOpenCustomHashSet c;
		try {
			c = (LongLinkedOpenCustomHashSet) super.clone();
		} catch (CloneNotSupportedException cantHappen) {
			throw new InternalError();
		}
		c.key = key.clone();
		c.containsNull = containsNull;
		c.link = link.clone();
		c.strategy = strategy;
		return c;
	}
	
Returns a hash code for this set. This method overrides the generic method provided by the superclass. Since equals() is not overriden, it is important that the value returned by this method is the same value as the one returned by the overriden method. 
Returns:a hash code for this set.
/**
	 * Returns a hash code for this set.
	 *
	 * This method overrides the generic method provided by the superclass. Since
	 * {@code equals()} is not overriden, it is important that the value returned by
	 * this method is the same value as the one returned by the overriden method.
	 *
	 * @return a hash code for this set.
	 */
	@Override
	public int hashCode() {
		int h = 0;
		for (int j = realSize(), i = 0; j-- != 0;) {
			while (((key[i]) == (0)))
				i++;
			h += (strategy.hashCode(key[i]));
			i++;
		}
		// Zero / null have hash zero.
		return h;
	}
	private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
		final LongIterator i = iterator();
		s.defaultWriteObject();
		for (int j = size; j-- != 0;)
			s.writeLong(i.nextLong());
	}

	private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
		s.defaultReadObject();
		n = arraySize(size, f);
		maxFill = maxFill(n, f);
		mask = n - 1;
		final long key[] = this.key = new long[n + 1];
		final long link[] = this.link = new long[n + 1];
		int prev = -1;
		first = last = -1;
		long k;
		for (int i = size, pos; i-- != 0;) {
			k = s.readLong();
			if ((strategy.equals((k), (0)))) {
				pos = n;
				containsNull = true;
			} else {
				if (!((key[pos = (it.unimi.dsi.fastutil.HashCommon.mix(strategy.hashCode(k))) & mask]) == (0)))
					while (!((key[pos = (pos + 1) & mask]) == (0)));
			}
			key[pos] = k;
			if (first != -1) {
				link[prev] ^= ((link[prev] ^ (pos & 0xFFFFFFFFL)) & 0xFFFFFFFFL);
				link[pos] ^= ((link[pos] ^ ((prev & 0xFFFFFFFFL) << 32)) & 0xFFFFFFFF00000000L);
				prev = pos;
			} else {
				prev = first = pos;
				// Special case of SET_PREV(newLink[pos], -1);
				link[pos] |= (-1L & 0xFFFFFFFFL) << 32;
			}
		}
		last = prev;
		if (prev != -1)
			// Special case of SET_NEXT(link[prev], -1);
			link[prev] |= -1 & 0xFFFFFFFFL;
		if (ASSERTS)
			checkTable();
	}
	private void checkTable() {
	}
}