class demo:
         def __init__(self,a,b,name):
                  self.a=a
                  self.b=b
                  self.name=name
         def add(self):
                  print("Addition of ",self.a,"and ",self.b, "is ",self.a+self.b)
         def sub(self):
                  print("Subtration of ",self.a,"and ",self.b, "is ",self.a-self.b)
         def reverse(self):
                  print(self.name[::-1])
         def sample(self):
                  print("Sample")
