@Test
public void testEquals_notEqual() {
Coordinate c1 = new Coordinate(3, -2);
Coordinate c2 = new Coordinate(-2, 3);
assertFalse(c1.equals(c2));
}
@Test
public void testEquals_equal() {
Coordinate c1 = new Coordinate(6, -2);
Coordinate c2 = new Coordinate(6, -2);
assertTrue(c1.equals(c2));
}