Andriy Makukha amakukha

Software developer with special interests in computational linguistics and history of UNIX.

amakukha / hash_djb2.py

Last active March 19, 2023 08:55 — forked from mengzhuo/hash_djb2.py

DJB2 Hash in Python

	# Proper (fast) Python implementations of Dan Bernstein's DJB2 32-bit hashing function
	#
	# DJB2 has terrible avalanching performance, though.
	# For example, it returns the same hash values for these strings: "xy", "yX", "z7".
	# I recommend using Murmur3 hash. Or, at least, FNV-1a or SDBM hashes below.

	import functools
	djb2 = lambda x: functools.reduce(lambda x,c: 0xFFFFFFFF & (x*33 + c), x, 5381)
	sdbm = lambda x: functools.reduce(lambda x,c: 0xFFFFFFFF & (x*65599 + c), x, 0)
	fnv1a_32 = lambda x: functools.reduce(lambda x,c: 0xFFFFFFFF & ((x^c)*0x1000193), x, 0x811c9dc5)