from functools import reduce
from operator import mul


with open("input", "r") as f:
    lines = f.read().splitlines()

lines = [line.split() for line in lines]

transposed = [[lines[j][i] for j in range(len(lines))] for i in range(len(lines[0]))]

s = 0

for line in transposed:
    operands, operator = list(map(int, line[:-1])), line[-1]
    if operator == "+":
        s += sum(operands)
    else:
        s += reduce(mul, operands, 1)

print(s)