1. 3,  2.1,  3.1, 4.2, 5.2, 6.4,
7.1, 8.3, 9.2, 10.1, 11.4, 12.1, 
13.1, 14.4, 15.4, 16.1, 17.4, 18.1,
19.1, 20.4, 21.4, 22.1, 23.4, 24.2, 25.2