def mul_div(exp):     #计算乘除

    while True:

        ret = re.search('[\d\.]+[\*\/]-?[\d\.]+', exp)

        if ret:

            atom_exp = ret.group()

            res = atom_cal(atom_exp)

            exp = exp.replace(atom_exp, res)

        else:

            return fomat_exp(exp)

def fomat_exp(exp):     #计算乘除后,统一符号

    exp=exp.replace('--','+')

    exp=exp.replace('-+','-')

    exp=exp.replace('++','+')

    exp=exp.replace('+-','-')

    return add_sub(exp)

def add_sub(exp):      #计算加减

    ret=re.findall('[\-\+]?[\d\.]+',exp)

    exp_sum=0

    for i in ret:

        exp_sum+=float(i)

    return exp_sum

def main(exp):         #主程序,先计算括号内的

    exp=exp.replace(' ','')

    while True:

        ret=re.search('\([^()]+\)',exp)

        if ret:

            inner_bracket=ret.group()

            res=str(mul_div(inner_bracket))

            exp = exp.replace(inner_bracket, res)

        else:break

    return mul_div(exp)

exp = '1 - 2 * ( (60-30 +(-40/5) * (9-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2) )'

print(main(exp))