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