#!/usr/bin/perl
use strict;
use warnings;
use 5.010;

die "No file names supplied!\n" unless @ARGV;
my $oldest_name = shift @ARGV;
my $oldest_age = -M $oldest_name;
        foreach (@ARGV) {
        my $age = -M;
        ($oldest_name, $oldest_age) = ($_, $age)
                if $age > $oldest_age;
}

printf "The oldest file was %s, and it was %.1f days old\n",
        $oldest_name, $oldest_age;