libboost-unordered

[brief]

Unordered associative containers

Part of collection of the Boost C++ Libraries.

For accessing data based on key lookup, the C++ standard library offers std::set, std::map, std::multiset and std::multimap. These are generally implemented using balanced binary trees so that lookup time has logarithmic complexity. That is generally okay, but in many cases a hash table can perform better, as accessing data has constant complexity, on average. The worst case complexity is linear, but that occurs rarely and with some care, can be avoided.

Also, the existing containers require a 'less than' comparison object to order their elements. For some data types this is impossible to implement or isn’t practical. In contrast, a hash table only needs an equality function and a hash function for the key.

With this in mind, unordered associative containers were added to the C++ standard. This is an implementation of the containers described in C++11, with some deviations from the standard in order to work with non-C++11 compilers and libraries.

License

Distributed under the Boost Software License, Version 1.0.

Properties

Build Status

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Directories

Name Purpose
doc documentation
example examples
include headers
test unit tests

More information

license BSL-1.0
project boost
url github.com/boostorg/unordered
doc-url www.boost.org/doc/libs/1_83_0/libs/unordered
topics C++Boost
4 Versions
version 1.83.0
repository https://pkg.cppget.org/1/stable
depends 12; libboost-assert, libboost-config, libboost-container-hash, libboost-core, libboost-move, libboost-mp11, libboost-predef, libboost-preprocessor, libboost-static-assert, libboost-throw-exception, libboost-tuple, libboost-type-traits
version 1.81.0+1
repository https://pkg.cppget.org/1/stable
depends 11; libboost-assert, libboost-config, libboost-container-hash, libboost-core, libboost-move, libboost-mp11, libboost-predef, libboost-preprocessor, libboost-throw-exception, libboost-tuple, libboost-type-traits
version 1.78.0
repository https://pkg.cppget.org/1/stable
depends 13; libboost-assert, libboost-config, libboost-container, libboost-container-hash, libboost-core, libboost-detail, libboost-move, libboost-predef, libboost-preprocessor, libboost-smart-ptr, libboost-throw-exception, libboost-tuple, libboost-type-traits
version 1.77.0+1
repository https://pkg.cppget.org/1/stable
depends 13; libboost-assert, libboost-config, libboost-container, libboost-container-hash, libboost-core, libboost-detail, libboost-move, libboost-predef, libboost-preprocessor, libboost-smart-ptr, libboost-throw-exception, libboost-tuple, libboost-type-traits