C++

Write a program that inputs from the user three numbers - the number of mattresses in stock at the beginning of the month, the number of mattresses received in during the month, and the number of mattresses sold during the month. The program should return the total number of mattresses currently in stock. Remember, you should always output to the user in textual form what is expected for keyboard entry. Make sure you have appropriate comments and output to explain the program's function. After