hh

fruit = input()
day_of_week = input()
quantity = float(input())
price = 0

if day_of_week == "Monday" or day_of_week == "Tuesday" or day_of_week == "Wednesday" or \
                              day_of_week == " Thursday" or day_of_week == "Friday":
    if fruit == "banana":
        price = 2.50
    if fruit == "apple":
        price = 1.20
    if fruit == "orange":
        price = 0.80
    if fruit == "grapefruit":
        price = 1.45
    if fruit == "kiwi":
        price = 2.70
    if fruit == "pineapple":
        price = 5.50
    if fruit == "grapes":
        price = 3.85
elif day_of_week == "Saturday" or day_of_week == "Sunday":
    if fruit == "banana":
        price = 2.70
    if fruit == "apple":
        price = 1.25
    if fruit == "orange":
        price = 0.90
    if fruit == "grapefruit":
        price = 1.60
    if fruit == "kiwi":
        price = 3.00
    if fruit == "pineapple":
        price = 5.60
    if fruit == "grapes":
        price = 4.20
if price == 0:
    print('error')
else:
    final_price = quantity * price
    print(f"{final_price:.2f}")