• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1[/
2    Copyright 2010 Neil Groves
3    Distributed under the Boost Software License, Version 1.0.
4    (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5/]
6[section:binary_search binary_search]
7
8[heading Prototype]
9
10``
11template<class ForwardRange, class Value>
12bool binary_search(const ForwardRange& rng, const Value& val);
13
14template<class ForwardRange, class Value, class BinaryPredicate>
15bool binary_search(const ForwardRange& rng, const Value& val, BinaryPredicate pred);
16``
17
18[heading Description]
19
20`binary_search` returns `true` if and only if the value `val` exists in the range `rng`.
21
22[heading Definition]
23
24Defined in the header file `boost/range/algorithm/binary_search.hpp`
25
26[heading Requirements]
27
28[*For the non-predicate versions of binary_search:]
29
30* `ForwardRange` is a model of the __forward_range__ Concept.
31* `Value` is a model of the `LessThanComparableConcept`.
32* The ordering of objects of type `Value` is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
33* `ForwardRange`'s value type is the same type as `Value`.
34
35[*For the predicate versions of binary_search:]
36
37* `ForwardRange` is a model of the __forward_range__ Concept.
38* `BinaryPredicate` is a model of the `StrictWeakOrderingConcept`.
39* `ForwardRange`'s value type is the same type as `Value`.
40* `ForwardRange`'s value type is convertible to `BinaryPredicate`'s argument type.
41
42[heading Precondition:]
43
44[*For the non-predicate version:]
45
46`rng` is ordered in ascending order according to `operator<`.
47
48[*For the predicate version:]
49
50`rng` is ordered in ascending order according to the function object `pred`.
51
52[heading Complexity]
53
54For non-random-access ranges, the complexity is `O(N)` where `N` is `distance(rng)`.
55
56For random-access ranges, the complexity is `O(log N)` where `N` is `distance(rng)`.
57
58[endsect]
59
60
61