#!/usr/bin/env python3

lines = (x.strip().replace(" ", "") for x in open("input.txt"))
operators = {
    "+": [2, lambda a, b: a+b],
    "*": [1, lambda a, b: a*b],
}


def calc(a, b, pop):
    return operators[pop][1](a, b)


def prec(pop):
    return operators.get(pop, [0])[0]


def evaluate(line):
    stack = []
    postfix = [0]
    for char in "("+line+")":
        if char.isdigit():
            postfix[-1] = postfix[-1] * 10 + int(char)
        elif char == '(':
            stack.append(char)
        elif char == ')':
            while prec(stack[-1]) > 0:
                postfix.append(calc(postfix.pop(), postfix.pop(), stack.pop()))
            stack.pop()
        elif char in operators:
            while prec(stack[-1]) > prec(char):
                postfix.append(calc(postfix.pop(), postfix.pop(), stack.pop()))
            stack.append(char)
            postfix.append(0)
        else:
            raise SystemError("Invalid char: "+char)
    return postfix[0]


print(sum(evaluate(line) for line in lines))