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I need to store a lookup table as an instance member in one of my classes. The table will be initialized when the object is constructed. Each "row" will have 3 "columns":
StringKey (e.g., "car")
EnumKey (e.g., LookupKeys.Car)
Value (e.g, "Ths is a car.")
I want to pick the data structure that will yield the best performance for doing lookups either by the StringKey or the EnumKey.
It's kind of awkward having 2 keys for the same dictionary value. I've never encountered this before, so I'm wondering what the norm is for this type of thing.
I could make a Key/Value/Value structure instead of Key/Key/Value, but I'm wondering what type of performance impact that would have.
Am I thinking about this all wrong?
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Looking at complexity analysis, Hashtables seem to be the most efficient for lookups.
In computer science, a lookup table is a data structure, usually an array or associative array, often used to replace a runtime computation with a simpler array indexing operation.
A heap will only let you search quickly for the minimum element (find it in O(1) time, remove it in O(log n) time). If you design it the other way, it will let you find the maximum, but you don't get both. To search for arbitrary elements quickly (in O(log n) time), you'll want the binary search tree. Good answer.
A lookup table is an array of data that maps input values to output values, thereby approximating a mathematical function. Given a set of input values, a lookup operation retrieves the corresponding output values from the table.
Well ... "Wrong" is a harsh way of putting it. I think that because the most common dictionary is "single key to value", and a lot of effort goes into providing efficient data structures for that (maps), it's often best to just use two of those, sharing the memory for the values if at all possible.
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