class Solution:
    @staticmethod
    def simple_calc(s: str) -> int:
        s = s.replace('--', '+')
        s = s.replace('+-', '-')
        total, num, plus = 0, 0, True
        for c in s:
            if '+' == c:
                total = total + int(num) if plus else total - int(num)
                num = 0
                plus = True
                continue
            if '-' == c:
                total = total + int(num) if plus else total - int(num)
                num = 0
                plus = False
                continue
            num = num*10 + int(c)

        total = total + int(num) if plus else total - int(num)

        return total

    def simplify(self, s: str) -> str:
        i, open = -1, -1
        for c in s:
            i += 1
            if '(' == c: open = i
            if ')' == c:
                s = s[0:open] + str(self.simple_calc(s[open + 1:i])) + s[i + 1:]
                return s
        return s

    def calculate(self, s: str) -> int:
        s = s.replace(' ', '')
        while '(' in s:
            s = self.simplify(s)
        return self.simple_calc(s)