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