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