public class Rectangle {

    int width;
    int height;

    int getArea() {
        return width * height;
    }

    int getPerimeter() {
        return 2 * (width + height);
    }

    public int getHeight() {
        return height;
    }

    public void setHeight(int _height) throws Exception {
        if (_height < 0 || _height > 20) {
            throw new Exception();
        }
        height = _height;
    }

    public int getWidth() {
        return width;
    }

    public void setWidth(int _width) throws Exception {
        if (_width < 0 || _width > 20) {
            throw new Exception();
        }
        width = _width;
    }
}