Small Shop

item = input()
city = input()
qty = float(input())

item_price = 0
if city == "Sofia":
    if item == "coffee":
        item_price = 0.5
    elif item == "water":
        item_price = 0.8
    elif item == "beer":
        item_price = 1.2
    elif item == "sweets":
        item_price = 1.45
    elif item == "peanuts":
        item_price = 1.6
elif city == "Plovdiv":
    if item == "coffee":
        item_price = 0.4
    elif item == "water":
        item_price = 0.7
    elif item == "beer":
        item_price = 1.15
    elif item == "sweets":
        item_price = 1.3
    elif item == "peanuts":
        item_price = 1.5
elif city == "Varna":
    if item == "coffee":
        item_price = 0.45
    elif item == "water":
        item_price = 0.7
    elif item == "beer":
        item_price = 1.1
    elif item == "sweets":
        item_price = 1.35
    elif item == "peanuts":
        item_price = 1.55

result = qty * item_price
print(result)