[(0, 0), (1, 0), (1, 1), (2, 1), (2, 2), (3, 2), (3, 3), (4, 3), (4, 4), (5, 4), (5, 5), (6, 5), (6, 6), (7, 6), (7, 7), (7, 8), (7, 9), (7, 10), (7, 11), (7, 12), (8, 12), (9, 12), (10, 12), (11, 12), (12, 12), (13, 12), (13, 13), (14, 13), (14, 14), (15, 14), (15, 15), (16, 15), (16, 16), (17, 16), (17, 17), (18, 17), (18, 18), (19, 18), (19, 19)]
Ilosc korkow to 39