# -*- coding: utf-8 -*-

import math

class pnt:
  def __init__(self, x, y):
    self.x = x
    self.y = y

  @classmethod
  def byAngle(self, a):
    return pnt(math.cos(a), math.sin(a))
  
  def d2(s):
    return s.x * s.x + s.y * s.y
  def d(s):
    return math.sqrt(s.d2())
  def __add__(a, b):
    return pnt(a.x + b.x, a.y + b.y)
  def __str__(s):
    return "pnt<" + str(s.x) + "," + str(s.y) + ">"

pnt.__sub__ = lambda a, b: pnt(a.x - b.x, a.y - b.y)

class circle:
  def __init__(self, x, y, r):
    self.p = pnt(x, y)
    self.r = r
  def __str__(s):
    return "circle<" + str(s.p) + "," + str(s.r) + ">"

p = pnt(2, 3)
q = pnt.byAngle(1.57)
print(p + q)
print(circle(2, 3, 4))