for(int i=0; i>=0; i++)
{
int price=0;
Console.WriteLine("Enter cup size blabla:");
string cupSize = Console.ReadLine();
switch(cupSize)
{
case ("small"):
case("Small"):
price=15;
break;

case("medium"):
case("Medןum"):
price=20;
break;

case("large"):
case("Large"):
price=25;
break;

default:
Console.WriteLine("Invalid blabla");
break;
}
if(price != 0)
Console.WriteLine("blabla " +price +"ISL");

Console.WriteLine("Press 1 for main menu\nPress 0 to exit");
int action = int.Parse(Console.ReadLine());
if(action == 0)
Console.WriteLine(1/action);
}