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