07. FruitShop

using System;

class FruitShop
{
    static void Main(string[] args)
    {
        var fruit = Console.ReadLine().ToLower();
        var day = Console.ReadLine().ToLower();
        var quantity = double.Parse(Console.ReadLine().ToLower());
        var price = -1.0;

        if (day == "monday" || day == "tuesday" || day == "wednesday" || day == "thursday" || day == "friday")
        {
            if (fruit == "banana")
            {
                price = quantity * 2.50;
            }
            else if (fruit == "apple")
            {
                price = quantity * 1.20;
            }
            else if (fruit == "orange")
            {
                price = quantity * 0.85;
            }
            else if (fruit == "grapefruit")
            {
                price = quantity * 1.45;
            }
            else if (fruit == "kiwi")
            {
                price = quantity * 2.70;
            }
            else if (fruit == "pineapple")
            {
                price = quantity * 5.50;
            }
            else if (fruit == "grapes")
            {
                price = quantity * 3.85;
            }
        }
        else if (day == "sunday" || day == "saturday")
        {
            if (fruit == "banana")
            {
                price = quantity * 2.70;
            }
            else if (fruit == "apple")
            {
                price = quantity * 1.25;
            }
            else if (fruit == "orange")
            {
                price = quantity * 0.90;
            }
            else if (fruit == "grapefruit")
            {
                price = quantity * 1.60;
            }
            else if (fruit == "kiwi")
            {
                price = quantity * 3.00;
            }
            else if (fruit == "pineapple")
            {
                price = quantity * 5.60;
            }
            else if (fruit == "grapes")
            {
                price = quantity * 4.20;
            }
        }
        if (price >= 0)
        {
            Console.WriteLine("{0:F2}", price);
        }
        else
        {
            Console.WriteLine("error");
        }
    }
}