gistfile1.md

 class Program
{
 static void Main()
 {
  
  //while (true)
  //{
   Console.SetCursorPosition(0, 0);
   Console.Write("initialVelocity_x:");
   double initialVelocity_x = int.Parse(Console.ReadLine()); // r.Next(10, 20);
   Console.Write("initialVelocity_y:");
   double initialVelocity_y = int.Parse(Console.ReadLine()); // r.Next(5, 20);
   physics.Ball ball=
   new physics.Ball(initialVelocity_x, initialVelocity_y);
   Console.WriteLine("return_time={0}", ball.CalculateReturnTime());
   ball.PrintPath();
   Console.SetCursorPosition(0, 3);
   while(true){
   Console.Write("enter some time t:");
   double t=double.Parse(Console.ReadLine());
   ball.GetPositionUnderGravityAtTime(t);
   Console.WriteLine("x={0},y={1}", ball.X, ball.Y);
  }
 }
}