0 0 1 1 1 1 1 1 1 1 0 0 1 2 3 4 5 6 7 8 0 0 1 2 3 4 5 6 7 8 0 0 0 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 0 2 2 2 2 2 2 2 [] [] [0] [0] [0] [0] [0] [0] [0] [0] [] [] [0] [0,1] [0,1,2] [0,1,2,3] [0,1,2,3,4] [0,1,2,3,4,5] [0,1,2,3,4,5,6] [0,1,2,3,4,5,6,7] [] [] [0] [0,1] [0,1,2] [0,1,2,3] [0,1,2,3,4] [0,1,2,3,4,5] [0,1,2,3,4,5,6] [0,1,2,3,4,5,6,7] [] [] [] [0,1] [0,1] [0,1] [0,1] [0,1] [0,1] [0,1] [1] [1] [1] [1] ['Hello'] ['World'] ['Hello'] ['World'] [] [] [['a'],['b','c']] ['a'] a [['d','e','f'],['g','h','i','j'],['k','l','m','n','o']] ['g','h','i','j'] h [['p','q','r','s','t','u'],['v','w','x','y','z','aa','bb'],['cc','dd','ee','ff','gg','hh','ii','jj'],['kk','ll','mm','nn','oo','pp','qq','rr','ss']] ['cc','dd','ee','ff','gg','hh','ii','jj'] ee [] [] [] [] [] [] [] [] [] [] [] []