Double Keyed Dictionary - social.msdn.microsoft.com

That being said, typically when you want a double-keyed dictionary, you should do something more like a HashSet with a struct, or a class where you've overridden GetHashCode (). A double-keyed dictionary is nothing more than a HashSet really, because you're logically treating the key and the value as a single unit. Coding Light - Illuminated Ideas and Algorithms in Software Coding Light ...

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