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Hash Tables, Hash Sets  RSS feed

 
Hunter McMillen
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Hey everyone,

I've coded in Java for a few semesters now, but not in any of my classes has a hash table or hash set/maps come up. I see people using them in their source code they post on this forum, but i'm not really sure what they do that's better than ways i code. So i was wondering if someone could fill me in on their uses and functionality.


Thanks.
Hunter.
 
Bear Bibeault
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You want to make an association between a key and a value? Map Man to the rescue!
 
Hunter McMillen
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a key to encrypt information?? I'm not really sure what you mean.
 
Bear Bibeault
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Let's say you want to convert state codes to their names.

What's better:
48 more times

or


?

 
Hunter McMillen
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so for something like what you just described would you need two maps?? one for the stateName and one for the keys? or does one map hold the name and the key ?
 
Bear Bibeault
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Look up java.util.Map. A single map equates the keys with their values. Some languages refer to these as Dictionaries I believe.
 
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