use List::Util qw( min max );

my @numbers;
@numbers = grep { /^\d+$/ } grep { -f } glob '*';

my $max = max@numbers;
my $previous = ($max)-1;

foreach (@numbers) {

  if (-z "$max") {

    if (-z "$previous") {
  
    print "previous conf: $previous \n";
    print "Latest conf: $max \n";
    printf "Ready for conf %d \n",++$max;
 
  }
 }
}