Letters Change Numbers

words = input().split()
total = 0


def position_in_alphabet(a: str):
    return ord(a.lower()) - 96


for word in words:
    word_total = 0
    number = int(word[1:-1])
    letter_before = word[0]
    letter_after = word[-1]

    if letter_before.isupper():
        word_total += number / position_in_alphabet(letter_before)
    else:
        word_total += number * position_in_alphabet(letter_before)

    if letter_after.isupper():
        word_total -= position_in_alphabet(letter_after)
    else:
        word_total += position_in_alphabet(letter_after)

    total += word_total

print(f'{round(total, 2):.2f}')