Answer to Question #231258 in C# for Syanda

Question

Create a windows application for a library which will request the user to input the number of books
checked out and the number of days they are overdue. Your program should then calculate and
displays the library fine, which is 20 cents per book per day for the first seven days a book is overdue,
then 50 cents per book per day for each additional day.

Answer 1

using System;


namespace Library
{
    public class Program
    {
        private static void Main(string[] args)
        {
            Console.WriteLine("Library program");

            Console.WriteLine(new string('-', 50));

            int books;
            int days;

            Console.WriteLine("Input number of books checked out: ");
            while(!int.TryParse(Console.ReadLine(), out books))
                Console.WriteLine("Wrong input. Please, try again.");

            Console.WriteLine("Input number of days books are overdue: ");
            while(!int.TryParse(Console.ReadLine(), out  days))
                Console.WriteLine("Wrong input. Please, try again.");

            Calculate(books, days);

            Console.WriteLine(new string('-', 50));
        }


        private static void Calculate(int books, int days)
        {
            int priceBeforeWeek = books * 20; // days <= 7
            int priceAfterWeek = books * 50; // days >= 7
            int priceInCents = 0;

            for (int i = 1; i <= days; i++)
            {
                if (i <= 7)
                    priceInCents += priceBeforeWeek;
                else
                    priceInCents += priceAfterWeek;
            }

            double result = (double)priceInCents / 100;

            Console.WriteLine($"Total: {result:C}"); //formatting
        }
    }
}