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

my $file='C:\temp\input.txt';

open(my $fh,'<',$file) or die("ERROR open $file ($!)\n");
my @content = <$fh>;
close $fh;

my @cleanedContent = grep { chomp && /^->/ } @content;

print scalar(@cleanedContent) . " --> größe des cleanedContent\n";