task8

using System;

public class Program
{
    public static void Main()
    {
        float bynToUsd = 9;
        float bynToEur = 9;
        float usdToByn = 6;
        float usdToEur = 6;
        float eurToByn = 9;
        float eurToUsd = 5;

        float bynWallet = 0;
        Console.WriteLine("Please input a balance of BYN wallet : ");
        bynWallet = Convert.ToSingle(Console.ReadLine());

        float usdWallet = 0;
        Console.WriteLine("Please input a balance of USD wallet : ");
        usdWallet = Convert.ToSingle(Console.ReadLine());

        float eurWallet = 0;
        Console.WriteLine("Please input a balance of EUR wallet : ");
        eurWallet = Convert.ToSingle(Console.ReadLine());

        uint chooseInput = 0;
        float changeCurrency = 0;
        bool isTransferMoney = true;
        bool isRun = true;

        while (isRun)
        {
            Console.WriteLine("\nBYN on wallet : " + bynWallet);
            Console.WriteLine("USD on wallet : " + usdWallet);
            Console.WriteLine("EUR on wallet : " + eurWallet + "\n\n");
            Console.WriteLine("What do you want to do?");
            Console.WriteLine("1. BYN -> USD.\n" +
                              "2. BYN -> EUR.\n" +
                              "3. USD -> BYN.\n" +
                              "4. USD -> EUR.\n" +
                              "5. EUR -> BYN.\n" +
                              "6. EUR -> USD.\n" +
                              "0. Exit");
            chooseInput = Convert.ToUInt32(Console.ReadLine());
            isTransferMoney = true;

            if (chooseInput == 0)
            {
                isRun = false;
                isTransferMoney = false;
            }
            else if (chooseInput > 6)
            {
                isTransferMoney = false;
                Console.WriteLine("\nChoose number is out of range.");
            }

            while (isTransferMoney)
            {
                Console.WriteLine("Please input count of money you want to change : ");
                changeCurrency = Convert.ToSingle(Console.ReadLine());

                switch (chooseInput)
                {
                    case 1:
                        if (bynWallet >= changeCurrency)
                        {
                            usdWallet += (changeCurrency / bynToUsd);
                            bynWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                    case 2:
                        if (bynWallet >= changeCurrency)
                        {
                            eurWallet += (changeCurrency / bynToEur);
                            bynWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                    case 3:
                        if (usdWallet >= changeCurrency)
                        {
                            bynWallet += (changeCurrency / usdToByn);
                            usdWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                    case 4:
                        if (usdWallet >= changeCurrency)
                        {
                            eurWallet += (changeCurrency / usdToEur);
                            usdWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                    case 5:
                        if (eurWallet >= changeCurrency)
                        {
                            bynWallet += (changeCurrency / eurToByn);
                            eurWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                    case 6:
                        if (eurWallet >= changeCurrency)
                        {
                            usdWallet += (changeCurrency / eurToUsd);
                            eurWallet -= changeCurrency;
                            isTransferMoney = false;
                        }
                        break;
                }

                if (isTransferMoney)
                    Console.WriteLine("Choosed amount of money is out range wallet.\n\n");
            }
        }
    }
}