use strict;

while (<DATA>) {
   chomp;
   my $input = $_;
   tr/$, +//d;
   if (/^[-]?\d+$/) {
      print "Acceptable: '$input' -> $_\n";
   } elsif (/^[-]?\d+\.[\d]+$/) {  ## problem
      print "Acceptable: '$input' -> ", int $_, "\n";
   } else {
      print "Not acceptable: '$input' -> $_\n";
   }
}

__DATA__
+30
-400
+20,0
-300.02
$ -50.1
-$ 500
- $ 60
 + $ 30.

##</code><code>##

Acceptable: '-400' -> -400
Acceptable: '+20,0' -> 200
Acceptable: '-300.02' -> -300
Acceptable: '$ -50.1' -> -50
Acceptable: '-$ 500' -> -500
Acceptable: '- $ 60' -> -60
Not acceptable: ' + $ 30.' -> 30.