In class, we've written code to determine whether a grade is an A, B,
C, D, or F. In this homework, you will allow the user to keep
inputting grade values until they decide they are done.

Sample execution:

--------
Input grade: 90
Grade is an: A
Type yes to input another: yes
Input grade: 80
Grade is an: B
Type yes to input another: yes
Input grade: 60
Grade is an: D
Type yes to input another: yes
Input grade: 59
Grade is an: F
Type yes to input another: yes
Input grade: 69
Grade is an: D
Type yes to input another: yes
Input grade: 70
Grade is an: C
Type yes to input another: no
---------


Use the above as sample inputs for your program and follow the handin script.
Modify file.cpp and file.exe to match your source and executable file names appropriately.

script handin2
cat file.cpp
g++ -o file.exe file.cpp 
./file.exe
90
yes
80
yes
60
yes
59
yes
69
yes
70
no
exit


To check your script, you can mail it to yourself:

mail yourlogin2@washcoll.edu < handin2