Create a program that does the same thing forwards and backwards, in different languages. “Different languages” does not include different versions of the same language.


This program can take any input and write anything to stdout and stderr. However, the program must output exactly the same things for the same input when run backwards in the other language. This explicitly includes anything written to stderr while the program is running, including errors. The length of the output from stdout and stderr must sum to at least 5. The minimum program length is 2 bytes.

  • This is a , so the answer with the most votes wins.
  • Comments are allowed, however the commented text must take up less than ¼ of the total program.
  • 3
    \$\begingroup\$ This is too broad because there is no real objective for the code, or criteria for judging one program better than another. \$\endgroup\$
    – feersum
    Sep 25 '15 at 0:06
  • 2
    \$\begingroup\$ Also, changing it to code-golf is no good because 1 would be valid in numerous languages. BTW, "derivative language" is not well defined at all. \$\endgroup\$ Sep 25 '15 at 0:10
  • \$\begingroup\$ @Calvin'sHobbies should I remove that? \$\endgroup\$
    – J F
    Sep 25 '15 at 0:11
  • \$\begingroup\$ @ETHproductions The challenge is making it do the same thing. I have also removed the derivative languages stipulation. \$\endgroup\$
    – J F
    Sep 25 '15 at 10:36
  • \$\begingroup\$ Would comments and programs that crash with errors be allowed? \$\endgroup\$ Sep 25 '15 at 13:53

BF + Foo

You saw it coming


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