risolutore algebrico

use Term::ReadLine;
$args = scalar(@ARGV);

$ENV{"PERL_RL"}="Gnu";

if ($args)
{
   $sum = join(" ", @ARGV);
   $sum =~ s/x/*/g;
   print "$sum = ", eval($sum), "\n";
   die "Error: $@\n" if $@;
   exit;
}

$term = new Term::ReadLine('=');

while (defined ($_ = $term->readline("> ")))
{
   chomp;
   push @a, eval($_);
   print "Errore: $@" if $@;
   $n = @a-1;
   $l = $a[$n];
   

print "quit\n";
exit;