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

    def __add__(self,other):
        return Vector(self.a + other.a , self.b + other.b)

    def __str__(self):
        return 'Vector (%d %d)'%(self.a,self.b)

v1= Vector(5,2)
v2=Vector(1,-2)
print v1 + v2
