fruit shop

fruit = input()
day_of_the_week = input()
quantity = float(input())
price = 0.00
is_valid = True

if day_of_the_week in "Monday Tuesday Wednesday Thursday Friday":

    if fruit == "banana":
        price = 2.50
    elif fruit == "apple":
        price = 1.20
    elif fruit == "orange":
        price = 0.85
    elif fruit == "kiwi":
        price = 2.70
    elif fruit == "pineapple":
        price = 5.50
    elif fruit == "grapes":
        price = 3.85
    else:
        is_valid = False

elif day_of_the_week in "Saturday Sunday":

    if fruit == "banana":
        price = 2.70
    elif fruit == "apple":
        price = 1.25
    elif fruit == "orange":
        price = 0.90
    elif fruit == "kiwi":
        price = 3.00
    elif fruit == "pineapple":
        price = 5.60
    elif fruit == "grapes":
        price = 4.20
    else:
        is_valid = False
else:
    is_valid = False

if is_valid:
    final_price = quantity * price
    print(f'{final_price:.2f}')
else:
    print('error')

''' Вариант 1'''
# if fruit not in "banana apple orange kiwi pineapple grapes" or day_of_the_week not in "Monday Tuesday Wednesday Thursday Friday Saturday Sunday":
#     print("error")
# else:
#     final_price = quantity * price
#     print(f'{final_price:.2f}')
''' Вариант 2'''
# if price == 0:
#     print("error")
# else:
#     final_price = quantity * price
#     print(f'{final_price:.2f}')