def evaluate_expression(s):
    tokens = tokenize(s)
    if not tokens:
        return 0
    result = int(tokens[0])
    for i in range(1, len(tokens), 2):
        op = tokens[i]
        num = int(tokens[i+1])
        if op == '+':
            result += num
        else:
            result -= num
    return result

def tokenize(s):
    tokens = []
    i = 0
    n = len(s)
    while i < n:
        if s[i] in '+-':
            # Check if it's a unary operator
            if not tokens or (tokens and tokens[-1] in '+-'):
                num_str = s[i]
                i += 1
                while i < n and s[i].isdigit():
                    num_str += s[i]
                    i += 1
                tokens.append(num_str)
            else:
                tokens.append(s[i])
                i += 1
        elif s[i].isdigit():
            num_str = ''
            while i < n and s[i].isdigit():
                num_str += s[i]
                i += 1
            tokens.append(num_str)
        else:
            i += 1
    return tokens

def process_expression(s):
    while '(' in s:
        left = s.index('(')
        right = s.index(')', left)
        substr = s[left+1:right]
        value = evaluate_expression(substr)
        s = s[:left] + str(value) + s[right+1:]
    return evaluate_expression(s)

S = input().strip()
print(process_expression(S))