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