What exactly are hashtables?

Posted by keg on Stack Overflow See other posts from Stack Overflow or by keg
Published on 2010-04-12T20:24:32Z Indexed on 2010/04/12 20:43 UTC
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hashtable

What are they and how do they work?
Where are they used?
When should I (not) use them?

I've heard the word over and over again, yet I don't know its exact meaning.

What I heard is that they allow associative arrays by sending the array key through a hash function that converts it into an int and then uses a regular array. Am I right with that?

(Notice: This is not my homework; I go too school but they teach us only the BASICs in informatics)

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What exactly are hashtables? - Developer IT

What exactly are hashtables?

hashtable

Related posts about hashtable

Copy hashtable to another hashtable using c++

Search Complexity of a Hashtable within a Hashtable?

How to fix the size of the Hashtable and find the whether it has fix size or not?

Hi, I have a C hashing routine which is behaving strangely?

Hashtable comparator problem

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