What is fastest way to find number of matches between arrays?

Posted by John Sheares on Stack Overflow See other posts from Stack Overflow or by John Sheares
Published on 2010-04-10T18:47:30Z Indexed on 2010/04/10 18:53 UTC
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c#

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array

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match

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optimization

Currently, I am testing every integer element against each other to find which ones match. The arrays do not contain duplicates within their own set. Also, the arrays are not always equal lengths. Are there any tricks to speed this up? I am doing this thousands of times, so it starting to become a bottle neck in my program, which is in C#.

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