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