use strict;
use warnings;
use car;

my $speed;
my $auto = new car("Opel Vectra",50000);

$speed = $auto->speed_up(25);
print "Speed is: $speed km\n";

$speed = $auto->speed_up(10);
print "Speed is: $speed km\n";

$speed  = $auto->slow_down(20);
print "Speed is: $speed km\n";