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