P$7\mathrm{.}8$

Define a structure Student with a first name,last name and course grade$($A$,$B$,$C$,$D$,$ or F$).$ Write a program that reads input in which each line has the first and last name and course grade separated by space. Upon reading the input, your program should print all students with grade A$,$ then all students grade B and so on$.$

Sample Output:

Enter the Student first name and last name, grade, please leave space

Allan James F

Richard John A

James Allan F

Ethan Clark B

John James D

Peter John C

John Peter A

Initial list:

F Allan James

A Richard John

F James Allan

B Ethan Clark

D John James

C Peter John

A John Peter

Students sorted by grade:

A Richard John

A John Peter

B Ethan Clark

C Peter John

D John James

F James Allan

F Allan James