import math
class Vector:
    def __init__(self, coords):
        self.coords = coords

    def __repr__(self):
        return self.coords.__repr__()

    def __add__(self, other):
        return Vector([a+b for a,b in zip(self.coords, other.coords)])
    
    def __sub__(self, other):
        return Vector([a-b for a,b in zip(self.coords, other.coords)])
   
    def __mul__(self, scale):
        return Vector([scale*a for a in self.coords])

    def __div__(self, scale):
        return Vector([a/scale for a in self.coords])

    def __rmul__(self, scale):
        return self*scale

    def dot(self, other):
        return sum([a*b for a,b in zip(self.coords, other.coords)])

    def mag(self):
        return math.sqrt(self.dot(self))