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algorithm - What is the best 32bit hash function for short strings (tag names)?

What is the best 32bit hash function for relatively short strings?

Strings are tag names that consist of English letters, numbers, spaces and some additional characters (#, $, ., ...). For example: Unit testing, C# 2.0.

I am looking for 'best' as in 'minimal collisions', performance is not important for my goals.

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I'm not sure if it's the best choice, but here is a hash function for strings:

The Practice of Programming (HASH TABLES, pg. 57)

/* hash: compute hash value of string */
unsigned int hash(char *str)
{
   unsigned int h;
   unsigned char *p;

   h = 0;
   for (p = (unsigned char*)str; *p != ''; p++)
      h = MULTIPLIER * h + *p;
   return h; // or, h % ARRAY_SIZE;
}

Empirically, the values 31 and 37 have proven to be good choices for the multiplier in a hash function for ASCII strings.


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