[(0,1),(1,2),(0,3),(2,4),(3,4),(1,5),(2,5),(3,6),(6,7),(7,8),(7,9),(4,10),(5,11),(6,12)]
[(0,1),(1,2),(2,3),(0,4),(3,5),(4,5),(2,6),(5,6),(1,7),(7,8),(4,9),(6,10),(3,11),(7,12)]
