Do it with C++ please

Use a switch statement to write the following program: The program prompts the user for a letter grade (of type char). The list of valid letter grades is: ABCDCF The program should consider both lower and upper case The program will then display the following messages: For grade 'A': display "Excellent" For grade 'B': display "Good" For Grade 'C': display "Average" For grade 'D' or ' E ': display "Below Average" For Grade 'F': display "Fail" For any other letter grade entered by users: display "Invalid Grade" Your test plan should include tests for each possible output, invalid input, and lowercase letters. Provide a total of 4 test cases: - You can choose a mix of test cases with uppercase inputs A, B, C, D, E, F or lowercase inputs a, b, c, d, e, f. - 1 invalid test case (provide a letter that is not within [A,F] or [a,f] )