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	/*
	* Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved.
	* 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
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	* by Oracle in the LICENSE file that accompanied this code.
	*
	* 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
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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	package java.util.stream;

	import java.util.Arrays;
	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.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 java.util.stream.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>
	*
	* <p>In cases where the stream implementation is able to optimize away the
	* production of some or all the elements (such as with short-circuiting
	* operations like {@code findFirst}, or in the example described in
	* {@link #count}), the action will not be invoked for those elements.
	*
	* @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);

	/**
	* Returns, if this stream is ordered, a stream consisting of the longest
	* prefix of elements taken from this stream that match the given predicate.
	* Otherwise returns, if this stream is unordered, a stream consisting of a
	* subset of elements taken from this stream that match the given predicate.
	*
	* <p>If this stream is ordered then the longest prefix is a contiguous
	* sequence of elements of this stream that match the given predicate. The
	* first element of the sequence is the first element of this stream, and
	* the element immediately following the last element of the sequence does
	* not match the given predicate.
	*
	* <p>If this stream is unordered, and some (but not all) elements of this
	* stream match the given predicate, then the behavior of this operation is
	* nondeterministic; it is free to take any subset of matching elements
	* (which includes the empty set).
	*
	* <p>Independent of whether this stream is ordered or unordered if all
	* elements of this stream match the given predicate then this operation
	* takes all elements (the result is the same as the input), or if no
	* elements of the stream match the given predicate then no elements are
	* taken (the result is an empty stream).
	*
	* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
	* stateful intermediate operation</a>.
	*
	* @implSpec
	* The default implementation obtains the {@link #spliterator() spliterator}
	* of this stream, wraps that spliterator so as to support the semantics
	* of this operation on traversal, and returns a new stream associated with
	* the wrapped spliterator. The returned stream preserves the execution
	* characteristics of this stream (namely parallel or sequential execution
	* as per {@link #isParallel()}) but the wrapped spliterator may choose to
	* not support splitting. When the returned stream is closed, the close
	* handlers for both the returned and this stream are invoked.
	*
	* @apiNote
	* While {@code takeWhile()} is generally a cheap operation on sequential
	* stream pipelines, it can be quite expensive on ordered parallel
	* pipelines, since the operation is constrained to return not just any
	* valid prefix, but the longest prefix of 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 takeWhile()} 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 takeWhile()} in parallel pipelines, switching to sequential
	* execution with {@link #sequential()} may improve performance.
	*
	* @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 to determine the longest
	* prefix of elements.
	* @return the new stream
	* @since 9
	*/
	default LongStream takeWhile(LongPredicate predicate) {
	Objects.requireNonNull(predicate);
	// Reuses the unordered spliterator, which, when encounter is present,
	// is safe to use as long as it configured not to split
	return StreamSupport.longStream(
	new WhileOps.UnorderedWhileSpliterator.OfLong.Taking(spliterator(), true, predicate),
	isParallel()).onClose(this::close);
	}

	/**
	* Returns, if this stream is ordered, a stream consisting of the remaining
	* elements of this stream after dropping the longest prefix of elements
	* that match the given predicate. Otherwise returns, if this stream is
	* unordered, a stream consisting of the remaining elements of this stream
	* after dropping a subset of elements that match the given predicate.
	*
	* <p>If this stream is ordered then the longest prefix is a contiguous
	* sequence of elements of this stream that match the given predicate. The
	* first element of the sequence is the first element of this stream, and
	* the element immediately following the last element of the sequence does
	* not match the given predicate.
	*
	* <p>If this stream is unordered, and some (but not all) elements of this
	* stream match the given predicate, then the behavior of this operation is
	* nondeterministic; it is free to drop any subset of matching elements
	* (which includes the empty set).
	*
	* <p>Independent of whether this stream is ordered or unordered if all
	* elements of this stream match the given predicate then this operation
	* drops all elements (the result is an empty stream), or if no elements of
	* the stream match the given predicate then no elements are dropped (the
	* result is the same as the input).
	*
	* <p>This is a <a href="package-summary.html#StreamOps">stateful
	* intermediate operation</a>.
	*
	* @implSpec
	* The default implementation obtains the {@link #spliterator() spliterator}
	* of this stream, wraps that spliterator so as to support the semantics
	* of this operation on traversal, and returns a new stream associated with
	* the wrapped spliterator. The returned stream preserves the execution
	* characteristics of this stream (namely parallel or sequential execution
	* as per {@link #isParallel()}) but the wrapped spliterator may choose to
	* not support splitting. When the returned stream is closed, the close
	* handlers for both the returned and this stream are invoked.
	*
	* @apiNote
	* While {@code dropWhile()} is generally a cheap operation on sequential
	* stream pipelines, it can be quite expensive on ordered parallel
	* pipelines, since the operation is constrained to return not just any
	* valid prefix, but the longest prefix of 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 dropWhile()} 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 dropWhile()} in parallel pipelines, switching to sequential
	* execution with {@link #sequential()} may improve performance.
	*
	* @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 to determine the longest
	* prefix of elements.
	* @return the new stream
	* @since 9
	*/
	default LongStream dropWhile(LongPredicate predicate) {
	Objects.requireNonNull(predicate);
	// Reuses the unordered spliterator, which, when encounter is present,
	// is safe to use as long as it configured not to split
	return StreamSupport.longStream(
	new WhileOps.UnorderedWhileSpliterator.OfLong.Dropping(spliterator(), true, predicate),
	isParallel()).onClose(this::close);
	}

	/**
	* 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> the type of the mutable result container
	* @param supplier a function that creates a new mutable 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 that must fold an element into a result
	* container.
	* @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 that accepts two partial result containers
	* and merges them, which must be compatible with the
	* accumulator function. The combiner function must fold
	* the elements from the second result container into the
	* first result container.
	* @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>.
	*
	* @apiNote
	* An implementation may choose to not execute the stream pipeline (either
	* sequentially or in parallel) if it is capable of computing the count
	* directly from the stream source. In such cases no source elements will
	* be traversed and no intermediate operations will be evaluated.
	* Behavioral parameters with side-effects, which are strongly discouraged
	* except for harmless cases such as debugging, may be affected. For
	* example, consider the following stream:
	* <pre>{@code
	* LongStream s = LongStream.of(1, 2, 3, 4);
	* long count = s.peek(System.out::println).count();
	* }</pre>
	* The number of elements covered by the stream source is known and the
	* intermediate operation, {@code peek}, does not inject into or remove
	* elements from the stream (as may be the case for {@code flatMap} or
	* {@code filter} operations). Thus the count is 4 and there is no need to
	* execute the pipeline and, as a side-effect, print out the elements.
	*
	* @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}.
	*
	* <p>The action of applying {@code f} for one element
	* <a href="../concurrent/package-summary.html#MemoryVisibility"><i>happens-before</i></a>
	* the action of applying {@code f} for subsequent elements. For any given
	* element the action may be performed in whatever thread the library
	* chooses.
	*
	* @param seed the initial element
	* @param f a function to be applied 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);
	Spliterator.OfLong spliterator = new Spliterators.AbstractLongSpliterator(Long.MAX_VALUE,
	Spliterator.ORDERED \| Spliterator.IMMUTABLE \| Spliterator.NONNULL) {
	long prev;
	boolean started;

	@Override
	public boolean tryAdvance(LongConsumer action) {
	Objects.requireNonNull(action);
	long t;
	if (started)
	t = f.applyAsLong(prev);
	else {
	t = seed;
	started = true;
	}
	action.accept(prev = t);
	return true;
	}
	};
	return StreamSupport.longStream(spliterator, false);
	}

	/**
	* Returns a sequential ordered {@code LongStream} produced by iterative
	* application of the given {@code next} function to an initial element,
	* conditioned on satisfying the given {@code hasNext} predicate. The
	* stream terminates as soon as the {@code hasNext} predicate returns false.
	*
	* <p>{@code LongStream.iterate} should produce the same sequence of elements as
	* produced by the corresponding for-loop:
	* <pre>{@code
	* for (long index=seed; hasNext.test(index); index = next.applyAsLong(index)) {
	* ...
	* }
	* }</pre>
	*
	* <p>The resulting sequence may be empty if the {@code hasNext} predicate
	* does not hold on the seed value. Otherwise the first element will be the
	* supplied {@code seed} value, the next element (if present) will be the
	* result of applying the {@code next} function to the {@code seed} value,
	* and so on iteratively until the {@code hasNext} predicate indicates that
	* the stream should terminate.
	*
	* <p>The action of applying the {@code hasNext} predicate to an element
	* <a href="../concurrent/package-summary.html#MemoryVisibility"><i>happens-before</i></a>
	* the action of applying the {@code next} function to that element. The
	* action of applying the {@code next} function for one element
	* <i>happens-before</i> the action of applying the {@code hasNext}
	* predicate for subsequent elements. For any given element an action may
	* be performed in whatever thread the library chooses.
	*
	* @param seed the initial element
	* @param hasNext a predicate to apply to elements to determine when the
	* stream must terminate.
	* @param next a function to be applied to the previous element to produce
	* a new element
	* @return a new sequential {@code LongStream}
	* @since 9
	*/
	public static LongStream iterate(long seed, LongPredicate hasNext, LongUnaryOperator next) {
	Objects.requireNonNull(next);
	Objects.requireNonNull(hasNext);
	Spliterator.OfLong spliterator = new Spliterators.AbstractLongSpliterator(Long.MAX_VALUE,
	Spliterator.ORDERED \| Spliterator.IMMUTABLE \| Spliterator.NONNULL) {
	long prev;
	boolean started, finished;

	@Override
	public boolean tryAdvance(LongConsumer action) {
	Objects.requireNonNull(action);
	if (finished)
	return false;
	long t;
	if (started)
	t = next.applyAsLong(prev);
	else {
	t = seed;
	started = true;
	}
	if (!hasNext.test(t)) {
	finished = true;
	return false;
	}
	action.accept(prev = t);
	return true;
	}

	@Override
	public void forEachRemaining(LongConsumer action) {
	Objects.requireNonNull(action);
	if (finished)
	return;
	finished = true;
	long t = started ? next.applyAsLong(prev) : seed;
	while (hasNext.test(t)) {
	action.accept(t);
	t = next.applyAsLong(t);
	}
	}
	};
	return StreamSupport.longStream(spliterator, 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.
	*
	* <p>This method operates on the two input streams and binds each stream
	* to its source. As a result subsequent modifications to an input stream
	* source may not be reflected in the concatenated stream result.
	*
	* @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 StackOverflowError}.
	*
	* @apiNote
	* To preserve optimization opportunities this method binds each stream to
	* its source and accepts only two streams as parameters. For example, the
	* exact size of the concatenated stream source can be computed if the exact
	* size of each input stream source is known.
	* To concatenate more streams without binding, or without nested calls to
	* this method, try creating a stream of streams and flat-mapping with the
	* identity function, for example:
	* <pre>{@code
	* LongStream concat = Stream.of(s1, s2, s3, s4).flatMapToLong(s -> s);
	* }</pre>
	*
	* @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();
	}
	}

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