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   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
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   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
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  package java.util.stream;
  
  import java.nio.charset.Charset;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.LongSummaryStatistics;
  import java.util.Objects;
  import java.util.OptionalDouble;
  import java.util.OptionalLong;
  import java.util.PrimitiveIterator;
  import java.util.Spliterator;
  import java.util.Spliterators;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.function.BiConsumer;
  import java.util.function.Function;
  import java.util.function.LongBinaryOperator;
  import java.util.function.LongConsumer;
  import java.util.function.LongFunction;
  import java.util.function.LongPredicate;
  import java.util.function.LongSupplier;
  import java.util.function.LongToDoubleFunction;
  import java.util.function.LongToIntFunction;
  import java.util.function.LongUnaryOperator;
  import java.util.function.ObjLongConsumer;
  import java.util.function.Supplier;
  
  /**
   * A sequence of primitive long-valued elements supporting sequential and parallel
   * aggregate operations.  This is the {@code long} primitive specialization of
   * {@link Stream}.
   *
   * <p>The following example illustrates an aggregate operation using
   * {@link Stream} and {@link LongStream}, computing the sum of the weights of the
   * red widgets:
   *
   * <pre>{@code
   *     long sum = widgets.stream()
   *                       .filter(w -> w.getColor() == RED)
   *                       .mapToLong(w -> w.getWeight())
   *                       .sum();
   * }</pre>
   *
   * See the class documentation for {@link Stream} and the package documentation
   * for <a href="package-summary.html">java.util.stream</a> for additional
   * specification of streams, stream operations, stream pipelines, and
   * parallelism.
   *
   * @since 1.8
   * @see Stream
   * @see <a href="package-summary.html">java.util.stream</a>
   */
  public interface LongStream extends BaseStream<Long, LongStream> {
  
      /**
       * Returns a stream consisting of the elements of this stream that match
       * the given predicate.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                  <a href="package-summary.html#Statelessness">stateless</a>
       *                  predicate to apply to each element to determine if it
       *                  should be included
       * @return the new stream
       */
      LongStream filter(LongPredicate predicate);
  
      /**
       * Returns a stream consisting of the results of applying the given
       * function to the elements of this stream.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *               <a href="package-summary.html#Statelessness">stateless</a>
       *               function to apply to each element
       * @return the new stream
       */
      LongStream map(LongUnaryOperator mapper);
  
      /**
       * Returns an object-valued {@code Stream} consisting of the results of
       * applying the given function to the elements of this stream.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">
       *     intermediate operation</a>.
       *
       * @param <U> the element type of the new stream
       * @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *               <a href="package-summary.html#Statelessness">stateless</a>
       *               function to apply to each element
       * @return the new stream
       */
      <U> Stream<U> mapToObj(LongFunction<? extends U> mapper);
  
      /**
       * Returns an {@code IntStream} consisting of the results of applying the
       * given function to the elements of this stream.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *               <a href="package-summary.html#Statelessness">stateless</a>
       *               function to apply to each element
       * @return the new stream
       */
      IntStream mapToInt(LongToIntFunction mapper);
  
      /**
       * Returns a {@code DoubleStream} consisting of the results of applying the
       * given function to the elements of this stream.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *               <a href="package-summary.html#Statelessness">stateless</a>
       *               function to apply to each element
       * @return the new stream
       */
      DoubleStream mapToDouble(LongToDoubleFunction mapper);
  
      /**
       * Returns a stream consisting of the results of replacing each element of
       * this stream with the contents of a mapped stream produced by applying
       * the provided mapping function to each element.  Each mapped stream is
       * {@link BaseStream#close() closed} after its contents
       * have been placed into this stream.  (If a mapped stream is {@code null}
       * an empty stream is used, instead.)
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *               <a href="package-summary.html#Statelessness">stateless</a>
       *               function to apply to each element which produces a
       *               {@code LongStream} of new values
       * @return the new stream
       * @see Stream#flatMap(Function)
       */
      LongStream flatMap(LongFunction<? extends LongStream> mapper);
  
      /**
       * Returns a stream consisting of the distinct elements of this stream.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">stateful
       * intermediate operation</a>.
       *
       * @return the new stream
       */
      LongStream distinct();
  
      /**
       * Returns a stream consisting of the elements of this stream in sorted
       * order.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">stateful
       * intermediate operation</a>.
       *
       * @return the new stream
       */
      LongStream sorted();
  
      /**
       * Returns a stream consisting of the elements of this stream, additionally
       * performing the provided action on each element as elements are consumed
       * from the resulting stream.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * <p>For parallel stream pipelines, the action may be called at
       * whatever time and in whatever thread the element is made available by the
       * upstream operation.  If the action modifies shared state,
       * it is responsible for providing the required synchronization.
       *
       * @apiNote This method exists mainly to support debugging, where you want
       * to see the elements as they flow past a certain point in a pipeline:
       * <pre>{@code
       *     LongStream.of(1, 2, 3, 4)
       *         .filter(e -> e > 2)
       *         .peek(e -> System.out.println("Filtered value: " + e))
       *         .map(e -> e * e)
       *         .peek(e -> System.out.println("Mapped value: " + e))
       *         .sum();
       * }</pre>
       *
       * @param action a <a href="package-summary.html#NonInterference">
       *               non-interfering</a> action to perform on the elements as
       *               they are consumed from the stream
       * @return the new stream
       */
      LongStream peek(LongConsumer action);
  
      /**
       * Returns a stream consisting of the elements of this stream, truncated
       * to be no longer than {@code maxSize} in length.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * stateful intermediate operation</a>.
       *
       * @apiNote
       * While {@code limit()} is generally a cheap operation on sequential
       * stream pipelines, it can be quite expensive on ordered parallel pipelines,
       * especially for large values of {@code maxSize}, since {@code limit(n)}
       * is constrained to return not just any <em>n</em> elements, but the
       * <em>first n</em> elements in the encounter order.  Using an unordered
       * stream source (such as {@link #generate(LongSupplier)}) or removing the
       * ordering constraint with {@link #unordered()} may result in significant
       * speedups of {@code limit()} in parallel pipelines, if the semantics of
       * your situation permit.  If consistency with encounter order is required,
       * and you are experiencing poor performance or memory utilization with
       * {@code limit()} in parallel pipelines, switching to sequential execution
       * with {@link #sequential()} may improve performance.
       *
       * @param maxSize the number of elements the stream should be limited to
       * @return the new stream
       * @throws IllegalArgumentException if {@code maxSize} is negative
       */
      LongStream limit(long maxSize);
  
      /**
       * Returns a stream consisting of the remaining elements of this stream
       * after discarding the first {@code n} elements of the stream.
       * If this stream contains fewer than {@code n} elements then an
       * empty stream will be returned.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">stateful
       * intermediate operation</a>.
       *
       * @apiNote
       * While {@code skip()} is generally a cheap operation on sequential
       * stream pipelines, it can be quite expensive on ordered parallel pipelines,
       * especially for large values of {@code n}, since {@code skip(n)}
       * is constrained to skip not just any <em>n</em> elements, but the
       * <em>first n</em> elements in the encounter order.  Using an unordered
       * stream source (such as {@link #generate(LongSupplier)}) or removing the
       * ordering constraint with {@link #unordered()} may result in significant
       * speedups of {@code skip()} in parallel pipelines, if the semantics of
       * your situation permit.  If consistency with encounter order is required,
       * and you are experiencing poor performance or memory utilization with
       * {@code skip()} in parallel pipelines, switching to sequential execution
       * with {@link #sequential()} may improve performance.
       *
       * @param n the number of leading elements to skip
       * @return the new stream
       * @throws IllegalArgumentException if {@code n} is negative
       */
      LongStream skip(long n);
  
      /**
       * Performs an action for each element of this stream.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * <p>For parallel stream pipelines, this operation does <em>not</em>
       * guarantee to respect the encounter order of the stream, as doing so
       * would sacrifice the benefit of parallelism.  For any given element, the
       * action may be performed at whatever time and in whatever thread the
       * library chooses.  If the action accesses shared state, it is
       * responsible for providing the required synchronization.
       *
       * @param action a <a href="package-summary.html#NonInterference">
       *               non-interfering</a> action to perform on the elements
       */
      void forEach(LongConsumer action);
  
      /**
       * Performs an action for each element of this stream, guaranteeing that
       * each element is processed in encounter order for streams that have a
       * defined encounter order.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @param action a <a href="package-summary.html#NonInterference">
       *               non-interfering</a> action to perform on the elements
       * @see #forEach(LongConsumer)
       */
      void forEachOrdered(LongConsumer action);
  
      /**
       * Returns an array containing the elements of this stream.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @return an array containing the elements of this stream
       */
      long[] toArray();
  
      /**
       * Performs a <a href="package-summary.html#Reduction">reduction</a> on the
       * elements of this stream, using the provided identity value and an
       * <a href="package-summary.html#Associativity">associative</a>
       * accumulation function, and returns the reduced value.  This is equivalent
       * to:
       * <pre>{@code
       *     long result = identity;
       *     for (long element : this stream)
       *         result = accumulator.applyAsLong(result, element)
       *     return result;
       * }</pre>
       *
       * but is not constrained to execute sequentially.
       *
       * <p>The {@code identity} value must be an identity for the accumulator
       * function. This means that for all {@code x},
       * {@code accumulator.apply(identity, x)} is equal to {@code x}.
       * The {@code accumulator} function must be an
       * <a href="package-summary.html#Associativity">associative</a> function.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @apiNote Sum, min, max, and average are all special cases of reduction.
       * Summing a stream of numbers can be expressed as:
       *
       * <pre>{@code
       *     long sum = integers.reduce(0, (a, b) -> a+b);
       * }</pre>
       *
       * or more compactly:
       *
       * <pre>{@code
       *     long sum = integers.reduce(0, Long::sum);
       * }</pre>
       *
       * <p>While this may seem a more roundabout way to perform an aggregation
       * compared to simply mutating a running total in a loop, reduction
       * operations parallelize more gracefully, without needing additional
       * synchronization and with greatly reduced risk of data races.
       *
       * @param identity the identity value for the accumulating function
       * @param op an <a href="package-summary.html#Associativity">associative</a>,
       *           <a href="package-summary.html#NonInterference">non-interfering</a>,
       *           <a href="package-summary.html#Statelessness">stateless</a>
       *           function for combining two values
       * @return the result of the reduction
       * @see #sum()
       * @see #min()
       * @see #max()
       * @see #average()
       */
      long reduce(long identity, LongBinaryOperator op);
  
      /**
       * Performs a <a href="package-summary.html#Reduction">reduction</a> on the
       * elements of this stream, using an
       * <a href="package-summary.html#Associativity">associative</a> accumulation
       * function, and returns an {@code OptionalLong} describing the reduced value,
       * if any. This is equivalent to:
       * <pre>{@code
       *     boolean foundAny = false;
       *     long result = null;
       *     for (long element : this stream) {
       *         if (!foundAny) {
       *             foundAny = true;
       *             result = element;
       *         }
       *         else
       *             result = accumulator.applyAsLong(result, element);
       *     }
       *     return foundAny ? OptionalLong.of(result) : OptionalLong.empty();
       * }</pre>
       *
       * but is not constrained to execute sequentially.
       *
       * <p>The {@code accumulator} function must be an
       * <a href="package-summary.html#Associativity">associative</a> function.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @param op an <a href="package-summary.html#Associativity">associative</a>,
       *           <a href="package-summary.html#NonInterference">non-interfering</a>,
       *           <a href="package-summary.html#Statelessness">stateless</a>
       *           function for combining two values
       * @return the result of the reduction
       * @see #reduce(long, LongBinaryOperator)
       */
      OptionalLong reduce(LongBinaryOperator op);
  
      /**
       * Performs a <a href="package-summary.html#MutableReduction">mutable
       * reduction</a> operation on the elements of this stream.  A mutable
       * reduction is one in which the reduced value is a mutable result container,
       * such as an {@code ArrayList}, and elements are incorporated by updating
       * the state of the result rather than by replacing the result.  This
       * produces a result equivalent to:
       * <pre>{@code
       *     R result = supplier.get();
       *     for (long element : this stream)
       *         accumulator.accept(result, element);
       *     return result;
       * }</pre>
       *
       * <p>Like {@link #reduce(long, LongBinaryOperator)}, {@code collect} operations
       * can be parallelized without requiring additional synchronization.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @param <R> type of the result
       * @param supplier a function that creates a new result container. For a
       *                 parallel execution, this function may be called
       *                 multiple times and must return a fresh value each time.
       * @param accumulator an <a href="package-summary.html#Associativity">associative</a>,
       *                    <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                    <a href="package-summary.html#Statelessness">stateless</a>
       *                    function for incorporating an additional element into a result
       * @param combiner an <a href="package-summary.html#Associativity">associative</a>,
       *                    <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                    <a href="package-summary.html#Statelessness">stateless</a>
       *                    function for combining two values, which must be
       *                    compatible with the accumulator function
       * @return the result of the reduction
       * @see Stream#collect(Supplier, BiConsumer, BiConsumer)
       */
      <R> R collect(Supplier<R> supplier,
                    ObjLongConsumer<R> accumulator,
                    BiConsumer<R, R> combiner);
  
      /**
       * Returns the sum of elements in this stream.  This is a special case
       * of a <a href="package-summary.html#Reduction">reduction</a>
       * and is equivalent to:
       * <pre>{@code
       *     return reduce(0, Long::sum);
       * }</pre>
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @return the sum of elements in this stream
       */
      long sum();
  
      /**
       * Returns an {@code OptionalLong} describing the minimum element of this
       * stream, or an empty optional if this stream is empty.  This is a special
       * case of a <a href="package-summary.html#Reduction">reduction</a>
       * and is equivalent to:
       * <pre>{@code
       *     return reduce(Long::min);
       * }</pre>
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>.
       *
       * @return an {@code OptionalLong} containing the minimum element of this
       * stream, or an empty {@code OptionalLong} if the stream is empty
       */
      OptionalLong min();
  
      /**
       * Returns an {@code OptionalLong} describing the maximum element of this
       * stream, or an empty optional if this stream is empty.  This is a special
       * case of a <a href="package-summary.html#Reduction">reduction</a>
       * and is equivalent to:
       * <pre>{@code
       *     return reduce(Long::max);
       * }</pre>
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @return an {@code OptionalLong} containing the maximum element of this
       * stream, or an empty {@code OptionalLong} if the stream is empty
       */
      OptionalLong max();
  
      /**
       * Returns the count of elements in this stream.  This is a special case of
       * a <a href="package-summary.html#Reduction">reduction</a> and is
       * equivalent to:
       * <pre>{@code
       *     return map(e -> 1L).sum();
       * }</pre>
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>.
       *
       * @return the count of elements in this stream
       */
      long count();
  
      /**
       * Returns an {@code OptionalDouble} describing the arithmetic mean of elements of
       * this stream, or an empty optional if this stream is empty.  This is a
       * special case of a
       * <a href="package-summary.html#Reduction">reduction</a>.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @return an {@code OptionalDouble} containing the average element of this
       * stream, or an empty optional if the stream is empty
       */
      OptionalDouble average();
  
      /**
       * Returns a {@code LongSummaryStatistics} describing various summary data
       * about the elements of this stream.  This is a special case of a
       * <a href="package-summary.html#Reduction">reduction</a>.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
       *
       * @return a {@code LongSummaryStatistics} describing various summary data
       * about the elements of this stream
       */
      LongSummaryStatistics summaryStatistics();
  
      /**
       * Returns whether any elements of this stream match the provided
       * predicate.  May not evaluate the predicate on all elements if not
       * necessary for determining the result.  If the stream is empty then
       * {@code false} is returned and the predicate is not evaluated.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * terminal operation</a>.
       *
       * @apiNote
       * This method evaluates the <em>existential quantification</em> of the
       * predicate over the elements of the stream (for some x P(x)).
       *
       * @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                  <a href="package-summary.html#Statelessness">stateless</a>
       *                  predicate to apply to elements of this stream
       * @return {@code true} if any elements of the stream match the provided
       * predicate, otherwise {@code false}
       */
      boolean anyMatch(LongPredicate predicate);
  
      /**
       * Returns whether all elements of this stream match the provided predicate.
       * May not evaluate the predicate on all elements if not necessary for
       * determining the result.  If the stream is empty then {@code true} is
       * returned and the predicate is not evaluated.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * terminal operation</a>.
       *
       * @apiNote
       * This method evaluates the <em>universal quantification</em> of the
       * predicate over the elements of the stream (for all x P(x)).  If the
       * stream is empty, the quantification is said to be <em>vacuously
       * satisfied</em> and is always {@code true} (regardless of P(x)).
       *
       * @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                  <a href="package-summary.html#Statelessness">stateless</a>
       *                  predicate to apply to elements of this stream
       * @return {@code true} if either all elements of the stream match the
       * provided predicate or the stream is empty, otherwise {@code false}
       */
      boolean allMatch(LongPredicate predicate);
  
      /**
       * Returns whether no elements of this stream match the provided predicate.
       * May not evaluate the predicate on all elements if not necessary for
       * determining the result.  If the stream is empty then {@code true} is
       * returned and the predicate is not evaluated.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * terminal operation</a>.
       *
       * @apiNote
       * This method evaluates the <em>universal quantification</em> of the
       * negated predicate over the elements of the stream (for all x ~P(x)).  If
       * the stream is empty, the quantification is said to be vacuously satisfied
       * and is always {@code true}, regardless of P(x).
       *
       * @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
       *                  <a href="package-summary.html#Statelessness">stateless</a>
       *                  predicate to apply to elements of this stream
       * @return {@code true} if either no elements of the stream match the
       * provided predicate or the stream is empty, otherwise {@code false}
       */
      boolean noneMatch(LongPredicate predicate);
  
      /**
       * Returns an {@link OptionalLong} describing the first element of this
       * stream, or an empty {@code OptionalLong} if the stream is empty.  If the
       * stream has no encounter order, then any element may be returned.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * terminal operation</a>.
       *
       * @return an {@code OptionalLong} describing the first element of this
       * stream, or an empty {@code OptionalLong} if the stream is empty
       */
      OptionalLong findFirst();
  
      /**
       * Returns an {@link OptionalLong} describing some element of the stream, or
       * an empty {@code OptionalLong} if the stream is empty.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
       * terminal operation</a>.
       *
       * <p>The behavior of this operation is explicitly nondeterministic; it is
       * free to select any element in the stream.  This is to allow for maximal
       * performance in parallel operations; the cost is that multiple invocations
       * on the same source may not return the same result.  (If a stable result
       * is desired, use {@link #findFirst()} instead.)
       *
       * @return an {@code OptionalLong} describing some element of this stream,
       * or an empty {@code OptionalLong} if the stream is empty
       * @see #findFirst()
       */
      OptionalLong findAny();
  
      /**
       * Returns a {@code DoubleStream} consisting of the elements of this stream,
       * converted to {@code double}.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @return a {@code DoubleStream} consisting of the elements of this stream,
       * converted to {@code double}
       */
      DoubleStream asDoubleStream();
  
      /**
       * Returns a {@code Stream} consisting of the elements of this stream,
       * each boxed to a {@code Long}.
       *
       * <p>This is an <a href="package-summary.html#StreamOps">intermediate
       * operation</a>.
       *
       * @return a {@code Stream} consistent of the elements of this stream,
       * each boxed to {@code Long}
       */
      Stream<Long> boxed();
  
      @Override
      LongStream sequential();
  
      @Override
      LongStream parallel();
  
      @Override
      PrimitiveIterator.OfLong iterator();
  
      @Override
      Spliterator.OfLong spliterator();
  
      // Static factories
  
      /**
       * Returns a builder for a {@code LongStream}.
       *
       * @return a stream builder
       */
      public static Builder builder() {
          return new Streams.LongStreamBuilderImpl();
      }
  
      /**
       * Returns an empty sequential {@code LongStream}.
       *
       * @return an empty sequential stream
       */
      public static LongStream empty() {
          return StreamSupport.longStream(Spliterators.emptyLongSpliterator(), false);
      }
  
      /**
       * Returns a sequential {@code LongStream} containing a single element.
       *
       * @param t the single element
       * @return a singleton sequential stream
       */
      public static LongStream of(long t) {
          return StreamSupport.longStream(new Streams.LongStreamBuilderImpl(t), false);
      }
  
      /**
       * Returns a sequential ordered stream whose elements are the specified values.
       *
       * @param values the elements of the new stream
       * @return the new stream
       */
      public static LongStream of(long... values) {
          return Arrays.stream(values);
      }
  
      /**
       * Returns an infinite sequential ordered {@code LongStream} produced by iterative
       * application of a function {@code f} to an initial element {@code seed},
       * producing a {@code Stream} consisting of {@code seed}, {@code f(seed)},
       * {@code f(f(seed))}, etc.
       *
       * <p>The first element (position {@code 0}) in the {@code LongStream} will
       * be the provided {@code seed}.  For {@code n > 0}, the element at position
       * {@code n}, will be the result of applying the function {@code f} to the
       * element at position {@code n - 1}.
       *
       * @param seed the initial element
       * @param f a function to be applied to to the previous element to produce
       *          a new element
       * @return a new sequential {@code LongStream}
       */
      public static LongStream iterate(final long seed, final LongUnaryOperator f) {
          Objects.requireNonNull(f);
          final PrimitiveIterator.OfLong iterator = new PrimitiveIterator.OfLong() {
              long t = seed;
  
              @Override
              public boolean hasNext() {
                  return true;
              }
  
              @Override
              public long nextLong() {
                  long v = t;
                  t = f.applyAsLong(t);
                  return v;
              }
          };
          return StreamSupport.longStream(Spliterators.spliteratorUnknownSize(
                  iterator,
                  Spliterator.ORDERED | Spliterator.IMMUTABLE | Spliterator.NONNULL), false);
      }
  
      /**
       * Returns an infinite sequential unordered stream where each element is
       * generated by the provided {@code LongSupplier}.  This is suitable for
       * generating constant streams, streams of random elements, etc.
       *
       * @param s the {@code LongSupplier} for generated elements
       * @return a new infinite sequential unordered {@code LongStream}
       */
      public static LongStream generate(LongSupplier s) {
          Objects.requireNonNull(s);
          return StreamSupport.longStream(
                  new StreamSpliterators.InfiniteSupplyingSpliterator.OfLong(Long.MAX_VALUE, s), false);
      }
  
      /**
       * Returns a sequential ordered {@code LongStream} from {@code startInclusive}
       * (inclusive) to {@code endExclusive} (exclusive) by an incremental step of
       * {@code 1}.
       *
       * @apiNote
       * <p>An equivalent sequence of increasing values can be produced
       * sequentially using a {@code for} loop as follows:
       * <pre>{@code
       *     for (long i = startInclusive; i < endExclusive ; i++) { ... }
       * }</pre>
       *
       * @param startInclusive the (inclusive) initial value
       * @param endExclusive the exclusive upper bound
       * @return a sequential {@code LongStream} for the range of {@code long}
       *         elements
       */
      public static LongStream range(long startInclusive, final long endExclusive) {
          if (startInclusive >= endExclusive) {
              return empty();
          } else if (endExclusive - startInclusive < 0) {
              // Size of range > Long.MAX_VALUE
              // Split the range in two and concatenate
              // Note: if the range is [Long.MIN_VALUE, Long.MAX_VALUE) then
              // the lower range, [Long.MIN_VALUE, 0) will be further split in two
              long m = startInclusive + Long.divideUnsigned(endExclusive - startInclusive, 2) + 1;
              return concat(range(startInclusive, m), range(m, endExclusive));
          } else {
              return StreamSupport.longStream(
                      new Streams.RangeLongSpliterator(startInclusive, endExclusive, false), false);
          }
      }
  
      /**
       * Returns a sequential ordered {@code LongStream} from {@code startInclusive}
       * (inclusive) to {@code endInclusive} (inclusive) by an incremental step of
       * {@code 1}.
       *
       * @apiNote
       * <p>An equivalent sequence of increasing values can be produced
       * sequentially using a {@code for} loop as follows:
       * <pre>{@code
       *     for (long i = startInclusive; i <= endInclusive ; i++) { ... }
       * }</pre>
       *
       * @param startInclusive the (inclusive) initial value
       * @param endInclusive the inclusive upper bound
       * @return a sequential {@code LongStream} for the range of {@code long}
       *         elements
       */
      public static LongStream rangeClosed(long startInclusive, final long endInclusive) {
          if (startInclusive > endInclusive) {
              return empty();
          } else if (endInclusive - startInclusive + 1 <= 0) {
              // Size of range > Long.MAX_VALUE
              // Split the range in two and concatenate
              // Note: if the range is [Long.MIN_VALUE, Long.MAX_VALUE] then
              // the lower range, [Long.MIN_VALUE, 0), and upper range,
              // [0, Long.MAX_VALUE], will both be further split in two
              long m = startInclusive + Long.divideUnsigned(endInclusive - startInclusive, 2) + 1;
              return concat(range(startInclusive, m), rangeClosed(m, endInclusive));
          } else {
              return StreamSupport.longStream(
                      new Streams.RangeLongSpliterator(startInclusive, endInclusive, true), false);
          }
      }
  
      /**
       * Creates a lazily concatenated stream whose elements are all the
       * elements of the first stream followed by all the elements of the
       * second stream.  The resulting stream is ordered if both
       * of the input streams are ordered, and parallel if either of the input
       * streams is parallel.  When the resulting stream is closed, the close
       * handlers for both input streams are invoked.
       *
       * @implNote
       * Use caution when constructing streams from repeated concatenation.
       * Accessing an element of a deeply concatenated stream can result in deep
       * call chains, or even {@code StackOverflowException}.
       *
       * @param a the first stream
       * @param b the second stream
       * @return the concatenation of the two input streams
       */
      public static LongStream concat(LongStream a, LongStream b) {
          Objects.requireNonNull(a);
          Objects.requireNonNull(b);
  
          Spliterator.OfLong split = new Streams.ConcatSpliterator.OfLong(
                  a.spliterator(), b.spliterator());
          LongStream stream = StreamSupport.longStream(split, a.isParallel() || b.isParallel());
          return stream.onClose(Streams.composedClose(a, b));
      }
  
      /**
       * A mutable builder for a {@code LongStream}.
       *
       * <p>A stream builder has a lifecycle, which starts in a building
       * phase, during which elements can be added, and then transitions to a built
       * phase, after which elements may not be added.  The built phase begins
       * begins when the {@link #build()} method is called, which creates an
       * ordered stream whose elements are the elements that were added to the
       * stream builder, in the order they were added.
       *
       * @see LongStream#builder()
       * @since 1.8
       */
      public interface Builder extends LongConsumer {
  
          /**
           * Adds an element to the stream being built.
           *
           * @throws IllegalStateException if the builder has already transitioned
           * to the built state
           */
          @Override
          void accept(long t);
  
          /**
           * Adds an element to the stream being built.
           *
           * @implSpec
           * The default implementation behaves as if:
           * <pre>{@code
           *     accept(t)
           *     return this;
           * }</pre>
           *
           * @param t the element to add
           * @return {@code this} builder
           * @throws IllegalStateException if the builder has already transitioned
           * to the built state
           */
          default Builder add(long t) {
              accept(t);
              return this;
          }
  
          /**
           * Builds the stream, transitioning this builder to the built state.
           * An {@code IllegalStateException} is thrown if there are further
           * attempts to operate on the builder after it has entered the built
           * state.
           *
           * @return the built stream
           * @throws IllegalStateException if the builder has already transitioned
           * to the built state
           */
          LongStream build();
      }
  }
  