def expression():
    global now
    ret = factor()

    while True:
        if S[now] == "+":
            now += 1
            ret += factor()
        elif S[now] == "-":
            now += 1
            ret -= factor()
        else:
            break
    
    return ret

def factor():
    global now
    if S[now] == "(":
        now += 1
        ret = expression()
        now += 1
        return ret
    else:
        return number()

def number():
    global now
    ret = ""
    
    while S[now].isdigit():
        ret += S[now]
        now += 1
    
    return int(ret)

S = input()
S += " "
now = 0
print(expression())