Efective way to avoid integer overflow when multiplying?

Posted by Jonathan on Stack Overflow See other posts from Stack Overflow or by Jonathan
Published on 2010-05-04T19:02:25Z Indexed on 2010/05/04 19:08 UTC
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Hi, I'm working on a hash function which gets a string as input.

Right now I'm doing a loop and inside the hash (an int variable) is being multiplied by a value and then the ASCII code for the current character is added to the mix.

hash = hash * seed + string[i]

But sometimes, if the string is big enough there is an integer overflow there, what can I do to avoid it while maintaining the same hash structure? Maybe a bit operation included inside the loop?

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Efective way to avoid integer overflow when multiplying? - Developer IT

Efective way to avoid integer overflow when multiplying?

c

hash

homework

Related posts about c

Related posts about hash

Problem with hash function: hash(1) == hash(1.0)

Hash table vs Hash list vs Hash tree?

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