use strict;
use warnings;

open (my $readfile,'<',"textfile.txt") or die $!;
while (my $line=<$readfile>) {
 chomp ($line);
 if ($line =~ /^\d+$/) {
   print "Digit gefunden: $line\n";
  }
  elsif ($line =~ /\A\w+\z/) {
      print "String gefunden: $line\n";
  }
}
close ($readfile);