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