Member Avatar for doublebond

Hi Guys,

Need some help.......

I want 2 read a huge file which contains binary data. Is it possible for me to make use of hash tables to read the same? if so, how can I do it.

If the key value of the hash function is and integer we can mod (%) the same with the size of the table (prime number). But, how can we do the same for binary data?

hash(key) = key % prime

Cheers

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  • Latest Post Latest Post by Tom Gunn
Member Avatar for Tom Gunn

Hash functions can handle more than just integers. The generic algorithms can hash any collection of bytes you give them:

unsigned int hash(void *key, int sz)
{
    unsigned char *p = (unsigned char*)key;
    unsigned hval = 0;

    for (int x = 0; x < sz; ++x)
    {
        hval = 31 * hval ^ p[x];
    }

    return hval;
}

A good place to start is here.

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