[(0,1),(1,2),(0,3),(2,4),(3,4),(1,5),(4,5),(2,6),(5,6),(3,7),(7,8),(6,9),(8,10),(9,11),(7,11),(9,12),(10,13),(11,14),(13,15),(14,16),(15,16),(8,17),(17,18),(16,19),(13,20),(12,21),(10,22),(12,23),(14,24),(18,25),(15,26),(17,27),(18,28)]
[(0,1),(0,2),(2,3),(3,4),(1,4),(4,5),(3,6),(1,7),(7,8),(6,8),(7,9),(6,9),(2,10),(10,11),(5,12),(9,13),(5,13),(10,14),(13,15),(11,15),(8,16),(12,17),(14,18),(17,19),(18,20),(14,21),(16,22),(18,23),(16,24),(11,25),(12,26),(15,27),(17,28)]
