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jed/LICENSE.txt

Forked from 140bytes/LICENSE.txt
Created September 7, 2011 14:20
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fletcher checksum
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index.js
function(a,b,c,d,e){for(b=c=d=0;e=a.charCodeAt(d++);c=(c+b)%255)b=(b+e)%255;return c<<8|b}
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LICENSE.txt
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 Jed Schmidt <http://jed.is>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
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package.json
{
"name": "fletcher checksum",
"description": "a javascript port of wikipedia's example C implementation of the fletcher checksum",
"keywords": [
"fletcher",
"checksum",
"hash"
]
}
Raw
test.html
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>51599</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
var fletcher = function(a,b,c,d,e){for(b=c=d=0;e=a.charCodeAt(d++);c=(c+b)%255)b=(b+e)%255;return c<<8|b}
document.getElementById( "ret" ).innerHTML = fletcher("140byt.es is totally rad!")
</script>
@p01
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p01 commented Sep 7, 2011

return b|c<<8 is 1 byte shorter ;)

@jed
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Author

jed commented Sep 7, 2011

good catch! tho i don't think i need to reverse the order, do i?

@monolithed
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fletcher('foo2e2e2') // 166 it's ok ?

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