IF: if($current && $resistance)
        {
            if($current =~ s/mA//i)
            {
                $current /= 1000;
            }
            else
            {
                
            }
        }
        else
        {
            print "Those aren't valid answers.\n";
            print "Please type that again, will ya?\n";
            
            print "Type the current of the circuit.\n";
            print "Add mA at the end of your answer\n";
            print "if your answer is in milliAmps.\n";
            
            $current = <STDIN>;
            chomp $current;
            
            print "Now type the resistance of the circuit.\n";
            
            $resistance = <STDIN>;
            chomp $resistance;
            
            goto IF;
        }