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