题解 | #加减乘除#

def mul(a):

    if a<2:
        return a
    return mul(a-1)*a


while True:
    try:
        s = input().split()
       
        if len(s) == 3:
            a = int(s[0])
            b = int(s[2])
            if s[1] == '+':
                res = a+b
            if s[1] == '-':
                res = a-b
            if s[1] == '*':
                res = a*b

            if s[1] == '/':
                if b==0:
                    res="error"
                else:
                    res = a/b
            if s[1] == '%':

                if b==0:
                    res="error"
                else:
                    res = a%b
        else:
            a = int(s[0])
            if s[1] == '!':
                res = mul(a)
        print(int(res))
    except:
        break