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Hash map optimized for search

I am looking for a card that has fixed keys (fixed during initialization), and this speeds up the search. It may not support adding / updating items later. Is there some kind of algorithm that looks through the list of keys and formulates a function to search faster later. In my case, the keys are strings.

Update:

Keys are not known at compile time. But during application initialization. After that there will be no additional inserts, but there will be many searches. Therefore, I want to optimize the optimization.

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google-sparsehash: http://code.google.com/p/google-sparsehash/

An extremely memory-efficient hash_map implementation. 2 bits/entry overhead! 
The SparseHash library contains several hash-map implementations, including 
implementations that optimize for space or speed.
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In a similar topic ((number) of elements known at compile time), I did the following: Search by a known set of integer keys . Low overhead, no perfect hash needed. Fortunately, it is in C; -)

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