iframe-proxy | Sunbelt Computer Software

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"""

Adler-32 is a checksum algorithm which was invented by Mark Adler in 1995.

Compared to a cyclic redundancy check of the same length, it trades reliability for

speed (preferring the latter).

Adler-32 is more reliable than Fletcher-16, and slightly less reliable than

Fletcher-32.[2]

source: https://en.wikipedia.org/wiki/Adler-32

"""

def adler32(plain_text: str) -> int:

"""

Function implements adler-32 hash.

Iterates and evaluates a new value for each character

>>> adler32('Algorithms')

363791387

>>> adler32('go adler em all')

708642122

"""

MOD_ADLER = 65521

a = 1

b = 0

for plain_chr in plain_text:

a = (a + ord(plain_chr)) % MOD_ADLER

b = (b + a) % MOD_ADLER

return (b << 16) | a

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