i need help coding in c++ please and thank you! I dont understand if i am supposed to declare my 3 numbers for the program to use before rule 1 where i ask the user the desired operation? Rule 3 says if the operation is valid ask the user for three numbers but what operation am i checking is valid? thank you

In this assignment, you will create a very particular calculator that works with 3 integer numbers at a time rather than the usual 2 in regular calculators. The calculator is also particular in that the desired operation is provided ahead of the numbers: 1. So, first, ask the user to enter the desired operation (use cin) and store the value in a variable named operation. The user input will consist of a single letter or symbol. Entering: a) 'a' or 'A' gives the average (shown as a fractional number) b) 'M' gives the largest number c) 'c' or 'C' gives the middle number 2. For example, entering 'a' or 'A' will get us the average. However, if the user input does not match any of the operations above, then the program must print an error message and exit. 3. If the operation is valid, then ask the user to enter three numbers. The numbers may be positive, negative, or zero. Expect them to be integers. If any input has decimals, your program will truncate the number. 4. Execute the requested operation and display the result(s). In all cases, the output is/are integers except for the average, which must be shown with 1 decimal. Also, for any program execution, only one of the operations indicated above needs to be executed