use Date::Manip::Date; 
$d = Date::Manip::Date->new; 
for (36,18,-17,7,-45) { 
    $d->parse(111111 . $_); 
    print substr $d->printf("%j%a%p%h" x 4), -$_, 1; 
} 
print "\n";
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Intermediate question

The date format has the four letters j a p h. Of the four letters in the output, which one do we extract from the output of which format letter?

Advanced question

This code will stop working about 45 days after it's posted. How can you fix the code so it works even after that date? I'll show a solution inside the spoiler, in case someone arrives here too late and wants to try this obfu.

use Date::Manip::Date; 
$d = Date::Manip::Date->new([setdate => "2023020700:00:00,UTC"]); 
for (36,18,-17,7,-45) { 
    $d->parse(111111 . $_); 
    print substr $d->printf("%j%a%p%h" x 4), -$_, 1; 
} 
print "\n";
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Expert question

Among the five loop iterations, the string is parsed in five different ways. How many of these are deliberate features of Date::Manip?

Update 2023-02-07T22:53Z: improved the obfuscation by changing the list of numbers from 36,18,2,7,-45 to 36,18,-17,7,-45. Now the obfuscation outputs JaPh instead of Japh and the five iterations parse the date in five different formats rather than just four. There's one drawback: