Cody Boone Ferguson
41abeda97a
In the line in README.md and index.html files that said:
### NOTICE to those who wish for a greater challenge
I added a ':' at the end of the line.
There were some entries that had a link fix in the index.html file but I
only looked up through 1995/leo as those still have to have a 'look and
feel' check and it would just slow things down.
2.1 KiB
To build:
make all
To use:
echo foo bar | ./dg
Try:
./try.sh
Judges' remarks:
Some C preprocessors got confused about single quotes in certain cases. In particular, the following source line:
b12(ase(bco(acp(bi(acp(bcp(acp(bpl(aqu(bqu(A))))))))))))))))))))))))))))))
sometimes has to be changed to:
b12(ase(bco(acp(bi(acp(bcp(acp(bpl('A'))))))))))))))))))))))))))))
particularly if the C preprocessor botches single quotes in cpp expansions, which we have done for the wider audience.
Author's remarks:
If my preprocessor could hack it, I could write this as one single line rather than 4, but when I do that I get a complaint "defines nested too deeply".
NOTICE to those who wish for a greater challenge:
If you want a greater challenge, don't read any further: just try to understand the program via the source.
If you get stuck, come back and read below for additional hints and information.
How this entry works:
This is another rot13 job (believe it or not) - the #defines are a
novel way of adding tokens: #define b12(x) 12 x means that at
some point in the source a 12 is followed by the compressed nested
#defines. The b12 gets the previous compression as an argument, and
prepends the 12, thus making another step in the recreation of the
source. The axx() #defines do the same, but add tokens after.
As for the rot13 algorithm, it relies on index(3) to find if the
character is in the set A-Za-z. l[] is an array that gets filled
with:
"nopqrstuvwxyzzzzabcdefghijklmmmmNOPQRSTUVWXYZZZZABCDEFGHIJKLMMMM"
If index(3) says the char is in the alphabet, then XOR the offset
with 16 to translate, and output, otherwise pass it unchanged.