in reply to understanding eval in HPOJ
When I typed echo $LANG from my BASH prompt it spit out the letter C. The script probably needs to make sure the $LANG variable is set, and is checking for its existence (some scripts are run without any environmental variables for security). Not sure what the evals are doing without looking up the variables they're using, and a quick google for the purpose of $LANG didn't turn up anything.
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