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