FruitShop

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace FruitShop
{
    class FruitShop
    {
        static void Main(string[] args)
        {
            string Fruit = Console.ReadLine().ToLower();
            string dayOfWeek = Console.ReadLine().ToLower();
            double quаntity = double.Parse(Console.ReadLine());

            string monday = "Monday";
            string tuesday = "Tuesday";
            string wednesday = "Wednesday";
            string thursday = "Thursday";
            string friday = "Friday";
            string saturday = "Saturday";
            string sunday = "Sunday";

            string banana = "banana";
            string apple = "apple";
            string orange = "orange";
            string grapefruit = "grapefruit";
            string kiwi = "kiwi";
            string pineapple = "pineapple";
            string grapes = "grapes";

            double priceOfProduct = -1.0;


            if (dayOfWeek == monday || dayOfWeek == tuesday ||
                dayOfWeek == wednesday || dayOfWeek == thursday ||
                dayOfWeek == friday)
            {
                if (Fruit == banana)
                {
                    priceOfProduct = 2.50;
                }
                else if (Fruit == apple)
                {
                    priceOfProduct = 1.20;
                }
                else if (Fruit == orange)
                {
                    priceOfProduct = 0.85;
                }
                else if (Fruit == grapefruit)
                {
                    priceOfProduct = 1.45;
                }
                else if (Fruit == kiwi)
                {
                    priceOfProduct = 2.70;
                }
                else if (Fruit == pineapple)
                {
                    priceOfProduct = 5.50;
                }
                else if (Fruit == grapes)
                {
                    priceOfProduct = 3.85;
                }
            }
            else if (dayOfWeek == saturday || dayOfWeek == sunday)
            {
                if (Fruit == banana)
                {
                    priceOfProduct = 2.70;
                }
                else if (Fruit == apple)
                {
                    priceOfProduct = 1.25;
                }
                else if (Fruit == orange)
                {
                    priceOfProduct = 0.90;
                }
                else if (Fruit == grapefruit)
                {
                    priceOfProduct = 1.60;
                }
                else if (Fruit == kiwi)
                {
                    priceOfProduct = 3.00;
                }
                else if (Fruit == pineapple)
                {
                    priceOfProduct = 5.60;
                }
                else if (Fruit == grapes)
                {
                    priceOfProduct = 4.20;
                }
            }
            if (priceOfProduct < 0)
            {
                Console.WriteLine("error");
            }
            else
            {
                double result = quаntity * priceOfProduct;
                Console.WriteLine($"{result:f2}");
            }
        }
    }
}