[(0,1),(1,2),(2,3),(0,3),(3,4),(2,5),(4,6),(5,6),(1,7),(4,7),(5,8),(7,8),(6,9),(9,10),(10,11),(8,12),(11,13),(11,14),(13,15),(14,15),(12,16),(14,17),(9,18),(10,18),(18,19),(13,19),(15,20),(12,21),(16,22),(22,23),(21,24),(22,24),(23,25),(20,26),(17,26),(16,27),(19,27),(24,28),(25,29),(26,30),(21,31),(25,32),(28,33),(27,34),(23,35),(17,36),(20,37),(28,38)]
[(0,1),(1,2),(1,3),(0,3),(2,4),(2,5),(4,5),(3,6),(5,7),(6,8),(4,9),(6,9),(7,10),(9,10),(8,11),(8,12),(7,13),(12,13),(10,14),(11,15),(14,15),(14,16),(13,16),(15,17),(17,18),(11,19),(17,20),(20,21),(18,21),(20,22),(16,23),(19,24),(21,24),(24,25),(18,25),(23,26),(22,27),(22,28),(28,29),(26,30),(27,31),(19,32),(27,33),(12,34),(25,35),(26,36),(23,37),(28,38)]
