class Calc():
    def __init__(self, a, b):
        self.a = a
        self.b = b

    def add(self):
        return self.a + self.b

    def mul(self):
        return self.a * self.b

    def div(self):
        return self.a / self.b

    def sub(self):
        return self.a - self.b

    def dii_int(self):
        return self.a //self.b

    def mod(self):
        return self.a % self.b


def main():
     a=4
     b=7
     calculator=Calc(a,b)
     print(str(a)+'+'+str(b)+'=',calculator.add())
     print(str(a) + '-' + str(b) + '=', calculator.sub())
     print(str(a) + '*' + str(b) + '=', calculator.mul())
     print(str(a) + '/' + str(b) + '=', calculator.div())
     print(str(a) + '//' + str(b) + '=', calculator.dii_int())
     print(str(a) + '%' + str(b) + '=', calculator.mod())


main()


#if __name__=='__main__':  # start here.
 #   print('')
  #  print('')