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