ceph/src/boost/libs/range/doc/reference/algorithm/binary_search.qbk

   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 ``
  11 template<class ForwardRange, class Value>
  12 bool binary_search(const ForwardRange& rng, const Value& val);
  13
  14 template<class ForwardRange, class Value, class BinaryPredicate>
  15 bool 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
  24 Defined 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
  54 For non-random-access ranges, the complexity is `O(N)` where `N` is `distance(rng)`.
  55
  56 For random-access ranges, the complexity is `O(log N)` where `N` is `distance(rng)`.
  57
  58 [endsect]
  59
  60