1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283 |
- [/
- 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:equal_range equal_range]
- [heading Prototype]
- ``
- template<
- class ForwardRange,
- class Value
- >
- std::pair<typename range_iterator<ForwardRange>::type,
- typename range_iterator<ForwardRange>::type>
- equal_range(ForwardRange& rng, const Value& val);
- template<
- class ForwardRange,
- class Value
- >
- std::pair<typename range_iterator<const ForwardRange>::type,
- typename range_iterator<const ForwardRange>::type>
- equal_range(const ForwardRange& rng, const Value& val);
- template<
- class ForwardRange,
- class Value,
- class SortPredicate
- >
- std::pair<typename range_iterator<ForwardRange>::type,
- typename range_iterator<ForwardRange>::type>
- equal_range(ForwardRange& rng, const Value& val, SortPredicate pred);
- template<
- class ForwardRange,
- class Value,
- class SortPredicate
- >
- std::pair<typename range_iterator<const ForwardRange>::type,
- typename range_iterator<const ForwardRange>::type>
- equal_range(const ForwardRange& rng, const Value& val, SortPredicate pred);
- ``
- [heading Description]
- `equal_range` returns a range in the form of a pair of iterators where all of the elements are equal to `val`. If no values are found that are equal to `val`, then an empty range is returned, hence `result.first == result.second`. For the non-predicate versions of `equal_range` the equality of elements is determined by `operator<`.
- For the predicate versions of `equal_range` the equality of elements is determined by `pred`.
- [heading Definition]
- Defined in the header file `boost/range/algorithm/equal_range.hpp`
- [heading Requirements]
- [*For the non-predicate versions:]
- * `ForwardRange` is a model of the __forward_range__ Concept.
- * `Value` is a model of the `LessThanComparableConcept`.
- * The ordering of objects of type `Value` is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
- * `ForwardRange`'s value type is the same type as `Value`.
- [*For the predicate versions:]
- * `ForwardRange` is a model of the __forward_range__ Concept.
- * `SortPredicate` is a model of the `StrictWeakOrderingConcept`.
- * `ForwardRange`'s value type is the same as `Value`.
- * `ForwardRange`'s value type is convertible to both of `SortPredicate`'s argument types.
- [heading Precondition:]
- For the non-predicate versions: `rng` is ordered in ascending order according to `operator<`.
- For the predicate versions: `rng` is ordered in ascending order according to `pred`.
- [heading Complexity]
- For random-access ranges, the complexity is `O(log N)`, otherwise the complexity is `O(N)`.
- [endsect]
|