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Questions tagged [bimap]

Bidirectional map is associative data structure where keys and values can switch their roles.

Bidirectional maps on wikipedia

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Is there a more efficient implementation for a bidirectional map?

I created a simple bidirectional map class that works by internally storing two std::map instances, with opposite key/value types, and providing a user-friendly interface: template class Bimap { std::map map1; …
Vittorio Romeo
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How to reverse a Map in Kotlin?

I am trying to reverse a Map in Kotlin. So far, I have come up with: mapOf("foo" to 42) .toList() .map { (k, v) -> v to k } .toMap() Is there any better way of doing this without using a middleman(middlelist)?
Grzegorz Piwowarek
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Is there a Boost.Bimap alternative in c++11?

Is there a usable alternative to Boost's bimap in C++0x? I would like to avoid Boost, but fully embrace C++11. If necessary, a slimmed down version of Boost's bimap would work for me (I need a constant bimap to switch between enums and corresponding…
rubenvb
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Boost::Bimap equivalent of bidirectional multimap

First part of the question is that I am trying to use boost::bimap, but from the documentation it is unclear to me how to define a bidirectional multimap. The second part of the question is that I need it to be a map in one direction and a multimap…
BlueTrin
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BiMap / 2-way hashmap in Kotlin

is there a bidirectional hashmap for kotlin? If not - what is the best way to express this in kotlin? Including guava to get the BiMap from there feels like shooting with a very big gun on a very little target - no solution that I can imagine…
ligi
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To instantiate BiMap Of google-collections in Java

How can you instantiate a Bimap of Google-collections? I've read the question Java: Instantiate Google Collection's HashBiMap A sample of my code import com.google.common.collect.BiMap; public class UserSettings { private Map…
Léo Léopold Hertz 준영
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Variadic typedefs, or "Bimaps done the C++0x way"

Short question: Can I typedef a variadic argument pack? I need template struct Forward { typedef T... args; };. Long version: I was thinking about reimplementing the excellent boost bimap in C++0x. Recall that a bimap of two types S…
Kerrek SB
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Replace vector and hash table with Boost.Bimap

I'm looking to replace a vector and a boost::unordered_map mapping string to indices in the former with a boost::bimap. What instantiation of bimap should I use? So far, I've come up with typedef bimap< …
Fred Foo
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Do we have a MultiBiMap?

As we know, there is the concept of BiMap and MultiMap but is there a MultiBiMap ? so what do I mean by this. In MultiMap you have one-to-many relationship between K and V, a single key can be associated to multiple value, hence the name. In BiMap…
AR5HAM
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Guava: java.lang.NoClassDefFoundError - com.google.common.collect.HashBiMap

I currently face the problem of java.lang.NoClassDefFoundError: com.google.common.collect.HashBiMap when using guava libraries downloaded from here: http://code.google.com/p/guava-libraries/ I already add guava-12.0.jar into my project as a…
Eric
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Bidirectional HashMap in Racket

Does Racket have a bidirectional hashmap? That is, a hash map that can in constant time, be given a key and look up the value, or given the value and look up the key? I would be happy for an API that looks something like this: #lang racket (define…
Leif Andersen
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Use of Boost Bimap in C++

C++ Boost has Bimap container that is a bidirectional map: http://www.boost.org/doc/libs/1_43_0/libs/bimap/doc/html/index.html Does anyone know the performance of Boost::bimap? I mean what's the time complexity of accessing an element in the map? Is…
user414585
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bimap implementation in modern C++ without Boost

This question has been asked before here I admit, but it's now 4 years ago so I dare to ask for an update: I need a way to add a tuple/pair to a container and search for both - the left and the right element efficiently. Boost has bimap and…
frans
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boost::bimap for enum

I'm trying to create a simple bi-directional lookup facility for enums in C++. I have one-way lookup working fine... enum MyEnum { One, Two, Three }; const boost::unordered_map MyEnumMap = map_list_of (One,…
salimoneus
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Use a custom allocator with boost::bimap

I am working on improving the performance of a program which uses both the Boost Graph Library and boost::bimap. Profiling revealed that most of the time was being spent in memory allocation and deallocation. Making the adjacency_list class of the…
Ryan Gabbard
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