import math

class Point3D():
    __slots__=('x' , 'y')

def evaluate (x , y):
    z = sin(x^2)*2 - y * cos(x * y) - x
    return z
def mkPoint3D(x , y):
    point = Point3D()
    point.x = x
    point.y = y
    point.evaluate = z
    return (x, y, z)
def maxPoint([x, y, z]):