We can't really answer that without knowing the format that the dates are in. The basic process, however, will probably consist of putting the dates in a hash keyed by the filenames and then sorting the keys of the hash based on the values. The sort will look something like:

my @files = sort { $hash{$a} <=> $hash{$b} } keys %hash;
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-sauoq
"My two cents aren't worth a dime.";