# Boost Multi-index Containers Library

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[Boost.MultiIndex](http://boost.org/libs/multi_index) provides a class template
named `multi_index_container` which enables the construction of containers
maintaining one or more indices with different sorting and access semantics.

## Learn about Boost.MultiIndex

* [Online documentation](https://boost.org/libs/multi_index)

## Install Boost.MultiIndex

* [Download Boost](https://www.boost.org/users/download/) and you're ready to go (this is a header-only library requiring no building).
* Using Conan 2: In case you don't have it yet, add an entry for Boost in your `conanfile.txt` (the example requires at least Boost 1.86):
```
[requires]
boost/[>=1.86.0]
```
<ul>If you're not using any compiled Boost library, the following will skip building altogether:</ul>

```
[options]
boost:header_only=True
```
* Using vcpkg: Execute the command
```
vcpkg install boost-multi-index
```
* Using CMake: [Boost CMake support infrastructure](https://github.com/boostorg/cmake)
allows you to use CMake directly to download, build and consume all of Boost or
some specific libraries.

## Support

* Join the **#boost** discussion group at [cpplang.slack.com](https://cpplang.slack.com/)
([ask for an invite](https://cppalliance.org/slack/) if you’re not a member of this workspace yet)
* Ask in the [Boost Users mailing list](https://lists.boost.org/mailman/listinfo.cgi/boost-users)
(add the `[multi_index]` tag at the beginning of the subject line)
* [File an issue](https://github.com/boostorg/multi_index/issues)

## Contribute

* [Pull requests](https://github.com/boostorg/multi_index/pulls) against **develop** branch are most welcome.
Note that by submitting patches you agree to license your modifications under the [Boost Software License, Version 1.0](http://www.boost.org/LICENSE_1_0.txt).