[(0,1),(0,2),(1,2),(2,3),(3,4),(3,5),(5,6),(6,7),(7,8),(5,8),(1,9),(7,10),(10,11),(10,12),(9,13),(6,14),(9,15),(4,16),(13,16),(4,17),(17,18),(8,19),(15,20),(11,21),(14,22),(19,23),(20,24),(12,24),(17,25),(24,25),(23,26),(11,27),(27,28),(22,29),(22,30),(12,31),(27,32),(16,33),(13,34),(14,35),(19,36),(28,37),(21,38),(18,39),(25,40),(26,41),(21,42),(15,43),(23,44),(18,45),(26,46),(20,47),(28,48)]
[(0,1),(1,2),(0,3),(1,4),(2,5),(4,6),(3,7),(4,8),(2,9),(9,10),(8,11),(5,12),(6,13),(7,13),(8,14),(14,15),(9,16),(6,17),(7,17),(10,18),(11,19),(13,20),(11,21),(16,22),(20,22),(16,23),(15,23),(20,24),(22,24),(14,25),(12,26),(23,27),(21,28),(26,29),(12,30),(26,31),(15,32),(3,33),(18,34),(18,35),(28,36),(28,37),(25,38),(27,39),(17,40),(25,41),(21,42),(24,43),(5,44),(10,45),(19,46),(27,47),(19,48)]
