marks = 55

if marks >= 80 and marks <= 100:
     print("You got A+")
else: 
    if marks >= 70 and marks <= 79:
        print("You got A")
    else:
        if marks >= 60 and marks <= 69:
            print("You got A-")
        else:
            if marks >= 50 and marks <= 59:
                print("You got B")
            else:
                if marks >= 40 and marks <= 49:
                    print("You got C")
                else:
                    if marks >= 33 and marks <= 39:
                        print("You got D")
                    else:
                        print("You got F")