about hash

[Wang Shaofu]

Hi
Looking for help!

hash_t HashKey::HashBytes(const void* bytes, int size) const
	{
	const unsigned char* cp = (const unsigned char*) bytes;
	hash_t h = 0;//unsigned int

	for ( int i = 0; i < size; ++i )
		// Overflow is okay here.
		h = (h >> 31) + (h << 1) + cp[i];
                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~This arithmetic make 
sure there is no collision????

	return h;
	}

Have a nice day!
Ciao
Cloud




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