my $pat = join '|', @dates;
my @files = grep /$pat/, @logfiles;

##</code><code>##

my @files;
foreach my $file( @logfiles ) { 
    foreach my $date( @dates ) { 
        if ( $file =~ /$date/ ) { 
            push @files, $file; 
            last;
        }
    }
}