WSJT-X/boost/libs/range/doc/reference/algorithm/merge.qbk

89 lines
3.7 KiB
Plaintext

[/
Copyright 2010 Neil Groves
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:merge merge]
[heading Prototype]
``
template<
class SinglePassRange1,
class SinglePassRange2,
class OutputIterator
>
OutputIterator merge(const SinglePassRange1& rng1,
const SinglePassRange2& rng2,
OutputIterator out);
template<
class SinglePassRange1,
class SinglePassRange2,
class OutputIterator,
class BinaryPredicate
>
OutputIterator merge(const SinglePassRange1& rng1,
const SinglePassRange2& rng2,
OutputIterator out,
BinaryPredicate pred);
``
[heading Description]
`merge` combines two sorted ranges `rng1` and `rng2` into a single sorted range by copying elements. `merge` is stable. The return value is `out + distance(rng1) + distance(rng2)`.
The two versions of `merge` differ by how they compare the elements.
The non-predicate version uses the `operator<()` for the range value type. The predicate version uses the predicate instead of `operator<()`.
[heading Definition]
Defined in the header file `boost/range/algorithm/merge.hpp`
[heading Requirements]
[*For the non-predicate version:]
* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
* `range_value<SinglePassRange1>::type` is a model of the `LessThanComparableConcept`.
* The ordering on objects of `range_value<SinglePassRange1>::type` is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.
[*For the predicate version:]
* `SinglePassRange1` is a model of the __single_pass_range__ Concept.
* `SinglePassRange2` is a model of the __single_pass_range__ Concept.
* `range_value<SinglePassRange1>::type` is the same as `range_value<SinglePassRange2>::type`.
* `BinaryPredicate` is a model of the `StrictWeakOrderingConcept`.
* `SinglePassRange1`'s value type is convertible to both `BinaryPredicate`'s argument types.
* `range_value<SinglePassRange1>::type` is convertible to a type in `OutputIterator`'s set of value types.
[heading Precondition:]
[heading For the non-predicate version:]
* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng1`, `y < x == false`.
* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]` of `rng2`, `y < x == false`.
* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* `[out, out + distance(rng1) + distance(rng2))` is a valid range.
[heading For the predicate version:]
* The elements of `rng1` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng1`, `pred(y, x) == false`.
* The elements of `rng2` are in ascending order. That is, for each adjacent element pair `[x,y]`, of `rng2`, `pred(y, x) == false`.
* The ranges `rng1` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* The ranges `rng2` and `[out, out + distance(rng1) + distance(rng2))` do not overlap.
* `[out, out + distance(rng1) + distance(rng2))` is a valid range.
[heading Complexity]
Linear. There are no comparisons if both `rng1` and `rng2` are empty, otherwise at most `distance(rng1) + distance(rng2) - 1` comparisons.
[endsect]