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