Hash Map Usage and Idea

Posted by Anand on Stack Overflow See other posts from Stack Overflow or by Anand
Published on 2010-03-23T10:26:31Z Indexed on 2010/03/23 10:33 UTC
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Hi,

I have been working in Java for the last 6 months and have been using Hash Maps

What is the basic idea of a Hash Map ? I am using it as it easy for me to store so much data with direct key references rather than having to iterate through an arraylist ?

Where is the power of Hash Map seen ? What is the scientific idea behind this data structure ?

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