def main():
    mark = raw_input("Enter the mark: ")
    if mark == "5":
        print "Your grade is A"
   
    if mark == "4":
        print "Your grade is B"
   
    if mark == "3":
        print "Your grade is C"
   
    if mark == "2":
        print "Your grade is D"
   
    if mark == "1":
        print "Your grade is E"

main()
       
