public static void Main()
Console.WriteLine("1- small , 2- Medium , 3- Large");
int UserChoice=int.Parse(Console.ReadLine());
Console.WriteLine("Invalid Choice");
Console.WriteLine("Do you want more?-- yes or no");
string UserDecision=Console.ReadLine();
switch(UserDecision.ToUpper())
Console.WriteLine("You have entered invalid input");
Console.WriteLine("Thank you for shopping with us");
Console.WriteLine("Bill amount - {0}",amount);