improve output in ZW script

src/perl/scripts2/ZW2019.pl

@@ -249,7 +249,7 @@ if(0)
                 system_code=>'$h->{mass_into_stars} += ($m1+$m2)*$prob;',
             }
         );
-    print "Mass into stars $h->{mass_into_stars}\n";
+    print "Mass into $h->{starcount} stars $h->{mass_into_stars}\n";
     exit;
 }