[]
[0,1]
[0,1,2,3]
[0,1,2,3,4,5]
[0,1,2,3,4,5,6,7]
[]
[0,1]
[0,1,2,3]
[0,1,2,3,4,5]
[0,1,2,3,4,5,6,7]
[]
[(0,0),(1,1)]
[(0,0),(1,1),(2,2),(3,3)]
[(0,0),(1,1),(2,2),(3,3),(4,4),(5,5)]
[(0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7)]
[]
[(0,1),(1,2)]
[(0,1),(1,2),(2,3),(3,4)]
[(0,1),(1,2),(2,3),(3,4),(4,5),(5,6)]
[(0,1),(1,2),(2,3),(3,4),(4,5),(5,6),(6,7),(7,8)]
[]
[(0,0),(1,1)]
[(0,0),(1,1),(2,2),(3,3)]
[(0,0),(1,1),(2,2),(3,3),(4,4),(5,5)]
[(0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7)]
[]
[(0,0),(1,1)]
[(0,0),(1,1),(2,2),(3,NULL)]
[(0,0),(1,1),(2,2),(3,NULL),(4,4),(5,5)]
[(0,0),(1,1),(2,2),(3,NULL),(4,4),(5,5),(6,6),(7,7)]