There are plenty of date and time related modules, but in this case Date::EzDate may in fact be easy:

my $date = Date::EzDate->new();

$date->{yeartwodigits} = 11;
$date->{yeardaybase1} = 32;
$date->{'myformat'} = '{year}{month number base 1}{day of month}';
print $date->{'myformat'};
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Make sure you read the docs about the 'year two digits' handling of the assumed century however!