public static void Main()
var fruit = Console.ReadLine();
var dayOfWeek = Console.ReadLine();
var quantity = double.Parse(Console.ReadLine());
if (dayOfWeek == "Saturday" || dayOfWeek == "Sunday")
else if (fruit == "apple")
else if (fruit == "orange")
else if (fruit == "grapefruit")
else if (fruit == "kiwi")
else if (fruit == "pineapple")
else if (fruit == "grapes")
else if(dayOfWeek == "Monday"
|| dayOfWeek == "Tuesday"
|| dayOfWeek == "Wednesday"
|| dayOfWeek == "Thursday"
|| dayOfWeek == "Friday")
else if (fruit == "apple")
else if (fruit == "orange")
else if (fruit == "grapefruit")
else if (fruit == "kiwi")
else if (fruit == "pineapple")
else if (fruit == "grapes")
Console.WriteLine("{0:F2}", price * quantity);
Console.WriteLine("error");