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"""

This algorithm (k=33) was first reported by Dan Bernstein many years ago in comp.lang.c

Another version of this algorithm (now favored by Bernstein) uses xor:

hash(i) = hash(i - 1) * 33 ^ str[i];

First Magic constant 33:

It has never been adequately explained.

It's magic because it works better than many other constants, prime or not.

Second Magic Constant 5381:

1. odd number

2. prime number

3. deficient number

4. 001/010/100/000/101 b

source: http://www.cse.yorku.ca/~oz/hash.html

"""

def djb2(s: str) -> int:

"""

Implementation of djb2 hash algorithm that

is popular because of it's magic constants.

>>> djb2('Algorithms')

3782405311

>>> djb2('scramble bits')

1609059040

"""

hash = 5381

for x in s:

hash = ((hash << 5) + hash) + ord(x)

return hash & 0xFFFFFFFF

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