sub print_results {
    my @top = param('toppings');
    print b('Customer name: '), param('customer'), br,
    "You ordered  ",
        param('no_unit'), ' unit of  ', param('cone'), ' cone.';
    print br;

    my $value = `perl compute_price.pl -type param('cone') -unit param('no_unit')`;

    # Still doesn't show the value. What did I do wrong??
    print 'Total price is', $value;
}