my $extreme = [365_000, undef];
    foreach (<*.log>) {
        $extreme = [-M, $_] if $extreme -> [0] > -M
    }
    my $newest = $extreme -> [1];

##</code><code>##

    @files = map {substr $_ => 18}
             sort
             map {sprintf "%017.10f %s" => -M, $_} <*.log>;