Several well-known Hash Algorithms

/*
**************************************** **********************************
**
* General Purpose hash function algorithms library *
**
* Author: Arash partow-2002 *
* URL: http://www.partow.net *
* URL: http://www.partow.net/programming/hashfunctions/index.html *
**
* Copyright notice :*
* Free use of the general purpose hash function algorithms library is *
* Permitted under the Guidelines and in accordance with the most current *
* Version of the common public license .*
* Http://www.opensource.org/licenses/cpl.php *
**
**************************************** **********************************
*/

Class generalhashfunctionlibrary
{

Public long rshash (string Str)
{
Int B = 378551;
Int A = 63689;
Long hash = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = hash * A + Str. charat (I );
A = A * B;
}

Return hash;
}
/* End of RS hash function */

Public long jshash (string Str)
{
Long hashing = 1315423911;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash ^ = (hash <5) + Str. charat (I) + (hash> 2 ));
}

Return hash;
}
/* End of JS hash function */

Public long pjwhash (string Str)
{
Long bitsinunsignedint = (long) (4*8 );
Long threequarters = (long) (bitsinunsignedint * 3)/4 );
Long oneeighth = (long) (bitsinunsignedint/8 );
Long highbits = (long) (0 xffffffff) <(bitsinunsignedint-oneeighth );
Long hash = 0;
Long test = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = (hash <oneeighth) + Str. charat (I );

If (test = hash & highbits )! = 0)
{
Hash = (hash ^ (test> threequarters ))&(~ Highbits ));
}
}

Return hash;
}
/* End of P. J. Weinberger hash function */

Public long elfhash (string Str)
{
Long hash = 0;
Long x = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = (hash <4) + Str. charat (I );

If (x = hash & 0xf0000000l )! = 0)
{
Hash ^ = (x> 24 );
}
Hash & = ~ X;
}

Return hash;
}
/* End of ELF hash function */

Public long bkdrhash (string Str)
{
Long seed = 131; // 31 131 1313 13131 131313 Etc ..
Long hash = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = (hash * seed) + Str. charat (I );
}

Return hash;
}
/* End of bkdr hash function */

Public long sdbmhash (string Str)
{
Long hash = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = Str. charat (I) + (hash <6) + (hash <16)-Hash;
}

Return hash;
}
/* End of sdbm hash function */

Public long djbhash (string Str)
{
Long hashing = 5381;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = (hash <5) + hash) + Str. charat (I );
}

Return hash;
}
/* End of djb hash function */

Public long dekhash (string Str)
{
Long hash = Str. Length ();

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = (hash <5) ^ (hash> 27) ^ Str. charat (I );
}

Return hash;
}
/* End of Dek hash function */

Public long bphash (string Str)
{
Long hash = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash = hash <7 ^ Str. charat (I );
}

Return hash;
}
/* End of BP hash function */

Public long fnvhash (string Str)
{
Long fnv_prime = 0x811c9dc5;
Long hash = 0;

For (INT I = 0; I <Str. Length (); I ++)
{
Hash * = fnv_prime;
Hash ^ = Str. charat (I );
}

Return hash;
}
/* End of FNV hash function */

Public long aphash (string Str)
{
Long hash = 0 xaaaaaaaa;

For (INT I = 0; I <Str. Length (); I ++)
{
If (I & 1) = 0)
{
Hash ^ = (hash <7) ^ Str. charat (I) ^ (hash> 3 ));
}
Else
{
Hash ^ = (~ (Hash <11) ^ Str. charat (I) ^ (hash> 5 )));
}
}

Return hash;
}
/* End of AP hash function */

}