class Dashboard {

    //Define variables with default values
    private int speedometer = 0;
    private int odometer = 0;
    private boolean engineLight = false;

    public Dashboard() {} //Blank constructor, variables have set defaults
    public Dashboard(int milesTravelled, int speed) {
        //Check if miles travelled is in bounds
        if (0 <= milesTravelled && milesTravelled <= 99999) {
            odometer = milesTravelled;
        } else {
            engineLight = true;
        }
        //Check if speed is in bounds
        if (0 <= speed && speed <= 100) {
            speedometer = speed;
        } else {
            engineLight = true;
        }
    }

    public void accelerate() {
        speedometer++; //Do the speeding up
        if (speedometer > 100) { //Check if speed is out of bounds
            speedometer = 0;
            engineLight = true;
        }
    }

    public void drive(int numMinutes) {
        if (numMinutes <= 720) { //Time cannot be bigger than 720
            odometer += speedometer * numMinutes / 60; //Add (speed in mph) * (time in minutes) * (1/60 hours to minutes conversion) to odometer value
            if (odometer > 99999) { //Check if miles traveled is out of bounds
                odometer = 0;
                engineLight = true;
            }
        }
    }

    public String toString() {
        String output = "Speedometer: " + speedometer + " MPH\nOdometer: ";

        //Calculate number of digits in odometer variable
        int digits = 0;
        int reading = odometer;
        if (reading == 0) {
            digits++; //When odometer is 0, it has 1 digit, not 0
        } else {
            //Divide number by 10 to count digits, ex: 1234 > 123 > 12 > 1 (4 digits)
            while (reading != 0) {
                digits++;
                reading /= 10;
            }
        }

        //Output zeros inversely proportional to amount of digits to make a total of 5
        //The NumberFormat class would be very useful here
        for (int i = 0; i < 5 - digits; i++) {
            output += "0";
        }
        output += odometer + "\nCheck Engine: O";

        //Outupt "On" if engineLight is true, "Off" otherwise
        if (engineLight) {
            return output + "n";
        } else {
            return output + "ff";
        }
    }

}