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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c,comp.programming
Subject: Re: C is not a low level language
Date: Thu, 28 Feb 2019 02:25:58 -0800
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Keith Thompson <kst-u@mib.org> writes:
[...]
>> #define _ -F<00||--F-OO--;
>> int F=00,OO=00;main(){F_OO();printf("%1.3f\n",4.*-F/OO/OO);}F_OO()
>> {
>>             _-_-_-_
>>        _-_-_-_-_-_-_-_-_
>>     _-_-_-_-_-_-_-_-_-_-_-_
>>   _-_-_-_-_-_-_-_-_-_-_-_-_-_
>>  _-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>>  _-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>>  _-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>>  _-_-_-_-_-_-_-_-_-_-_-_-_-_-_
>>   _-_-_-_-_-_-_-_-_-_-_-_-_-_
>>     _-_-_-_-_-_-_-_-_-_-_-_
>>         _-_-_-_-_-_-_-_
>>             _-_-_-_
>> }
>>
>>
>> 	... but far from readable.
>
> That program is from the 1989 IOCCC (International Obfuscated C Code
> Contest).  It doesn't produce the expected result because it makes an
> assumption about the behavior of the C preprocessor.

Correction: 1988.

> Changing the #define line to
>
> #define _ F-->00||F-OO--;
>
> fixes the problem.  (It still produces some warnings, and strictly
> speaking has undefined behavior, fixable by updating adding an #include
> directive and updating the function declarations.)
>
> With this change, the output is
>
>     3.141
>
> https://ioccc.org/1988/westley.c
> https://ioccc.org/1988/westley.hint

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */