You will write a C# program for a small bookstore to track daily number of sold books, number

of books received as donations, and current inventory. The inventory is the total number of books

available for sale and is updated as books are sold or donated. For this bookstore, the inventory

can increase with donations and decrease with sales. The bookstore maintains a maximum

inventory size due to space limitations$.$ Define a constant $($MAX$\_$INVENTORY$)$ to maintain this

maximum inventory size. You can assign a value of your choice for this constant. The program

will prompt the user to input one of four options: $$S$$ or $$s$($to enter a sale transaction$),$D$$ or $$d$$

$($to enter a donation$),$P$$ or $$p$($to print the totals and current inventory$),$Q$$ or $$q$($to quit$).$ Your

program will utilize a loop to ensure only valid choices are made. The program continues to accept

inputs until $\text{'}$Q$\text{'}$ or $\text{'}$q$\text{'}$ is entered. Based on the user input, in the Main method, you will use a switch

statement to call the following four methods as appropriate:

A$)$ InputNumberOfBooks: This method prompts the user to enter an integer value $($number

of books$)$ when they want to record a sale or donation. This method will take an integer

input from the user and return this value to the Main method. The returned amount will

then be passed as a parameter to the appropriate method $($ProcessSale or

AcceptDonation$).$ The method signature will be:

public static int InputNumberOfBooks$()$

B$)$ ProcessSale: This method takes three arguments: one value and two references. The callby$-$value parameter will accept the number of books sold. The reference parameters will

accept the current inventory and the total number of books sold. The total book sales and

the inventory will be updated in this method. The method signature will be:

public static void ProcessSale$($int numberOfBooks, ref int inventory, ref int totalSales$)$

C$)$ AcceptDonation: This method takes four arguments: two values and two references. The

call$-$by$-$value parameters will accept the number of books donated and the maximum

inventory size. The reference parameters will accept the current inventory and the total

donations. The total donations and the inventory will be updated by adding the number of

donated books. Donations will be accepted only if the inventory does not exceed the

maximum inventory size. The method will return a string which will be either $$Donation

accepted$$ or $$Donation not accepted$.$ This returned string will be printed in the Main

method. The method signature will be:

public static string AcceptDonation$($int numberOfBooks, int maxInventory, ref int

inventory, ref int totalDonations$)$

D$)$ PrintTotals: This method will accept three call$-$by$-$value parameters: total sales, total

donations, and current inventory. It will print these values to provide a summary of the

bookstore's operations for the day. The method signature will be:

public static void PrintTotals$($int totalSales, int totalDonations, int inventory$)$

Submission Instructions:

Important: You are NOT allowed to use arrays for this assignment. Do NOT use any C#

language$-$features that has not been taught in the class. Check the lecture slides to verify this.

Some concepts may exist in the textbook, but we did not learn those in the class. You are NOT

allowed to use these. Submissions that utilize any C# language$-$features beyond the lecture slides

will automatically receive $0$ in the assignment.