public class BallTossSimulator3 {

    double vy;

    public double run (double stopTime, double initVelocity, double targetHeight, boolean beforeMaxHeight)
    {
	// Initialize variables.
        double a = 9.8;
        vy = initVelocity;
        double y = 0;
        double t = 0;
        double delT = 0.01;

        boolean maxReached = false;

	while (true) {
	    // Update time.
	    t += delT;

            // Increase velocity accordingly.
	    vy = vy - delT * a;

            // Increase distance according to velocity.
            double nextY = y + delT * vy;

            double prevY = y;
            y = nextY;

            if (y < prevY) {
                maxReached = true;
            }
            
            if (beforeMaxHeight) {
                if (y > targetHeight) {
                    // Done.
                    break;
                }
            }
            else if (maxReached) {
                if (y < targetHeight) {
                    // Done.
                    break;
                }
            }
            
	    if ((t >= stopTime) || (y <= 0)) {
                break;
	    }
	}

        return y;
    }

    
    public double getV ()
    {
        return vy;
    }

}