#
#  Convert a letter grade entered by the user to the equivalent number of
#  grade points.
#


#
#  Read the letter grade from the user.
#
letter = input("Enter a letter grade: ")

#
#  Identify the number of grade points for the entered letter.
#
if letter == "A" or letter == "a":
  gp = 4.0
elif letter == "B" or letter == "b":
  gp = 3.0
elif letter == "C" or letter == "c":
  gp = 2.0
elif letter == "D" or letter == "d":
  gp = 1.0
elif letter == "F" or letter == "f":
  gp = 0.0
else:
  gp = -1.0


#
#  Display the number of grade points.
#
if gp >= 0:
  print(f"A(n) {letter} is equal to {gp} grade points.")
else:
  print("That wasn't a valid letter grade.")