import sys


def input():
    return sys.stdin.readline()[:-1]


def main():
    S = input()

    nums = []
    flag = False
    i = 0
    while i < len(S):
        if S[i] == "(":
            k, n = 1, 0
            flag = True
        elif S[i] == ")":
            nums.append(n)
            flag = False
        elif flag:
            if S[i] == "-":
                k = -1
            elif S[i] == "+":
                k = 1
            else:
                n += int(S[i]) * k
        i += 1

    ans = 0
    flag = True
    i, j, k = 0, 0, 1
    while i < len(S):
        if S[i] == "(":
            ans += nums[j] * k
            j += 1
            flag = False
        elif S[i] == ")":
            flag = True
        elif flag:
            if S[i] == "-":
                k = -1
            elif S[i] == "+":
                k = 1
            else:
                ans += int(S[i]) * k
        i += 1

    print(ans)


if not __debug__:
    f = open(sys.argv[1], "r")
    sys.stdin = f

main()