class RoomModel { // In your model .java file
    private static final int WIDTH = 4;
    private static final int HEIGHT = 5;

    private int steps; //USE CONSTRUCTOR TO INITIALIZE.
    private Position = new Position();

    static class Position {
    // Not necessary to have nested class
    // but it is a good approach
        public int xPosition;
        public int yPosition;
    }

    // YOU WILL WRITE THESE METHODS
    public boolean canXXXX(){}
    public void moveXXXX(){}
    public void updateSteps(){}
    public int getSteps(){}
}
class Controller {  // In your controller .java file
    public void onButtonClick(view View){
        if (model.canMoveXXXX()) {
            // the x- and y-coordinate of the robot are updated only if the robot can move (use your canGo????
            // methods to determine if robot can move), and
            model.moveXXX();
        }
        //the counter is incremented even if the robot cannot move in the direction corresponding to the pressed button.
        model.updateSteps();
        //We want to distinguish those buttons that capture directions in which the robot can move from the buttons
        //representing directions in which the robot cannot move. The former should be green, whereas the latter should be red.
        updateButtonStatus();
        updateLabel();
    }
    public void updateButtonStatus(){
        ButtonXXX.setBgColor((model.canMoveXXX())? Green : Red);
    }
    public void updateLabel(){}  //method this.t(); in Prof's Webpage
}