import math
text: str

with open("input.txt") as f:
    text = f.read()

total: int  = 0

lines: list[str] = text.splitlines()
numbers: list[list[int]] = [[int(nb_str) for nb_str in line.split(" ") if len(nb_str)] for line in lines[:-1]]
for i, operator in enumerate([operator for operator in lines[-1].split(" ") if len(operator)]):
    if (operator == "+"):
        total += sum([numbers[j][i] for j in range(len(lines) - 1)])
    elif (operator == "*"):
        total += math.prod([numbers[j][i] for j in range(len(lines) - 1)])

print(total)