From root: ancestors: preceding: self: descendant: a b c d e f g h i j k l m n o p following: ------------------------------------------------ From a: ancestors: preceding: self: a descendant: b c d e f g h i j k l m n o p following: ------------------------------------------------ From b: ancestors: a preceding: self: b descendant: c d e f g h i j following: k l m n o p ------------------------------------------------ From c: ancestors: a b preceding: self: c descendant: following: d e f g h i j k l m n o p ------------------------------------------------ From d: ancestors: a b preceding: c self: d descendant: e f following: g h i j k l m n o p ------------------------------------------------ From e: ancestors: a b d preceding: c self: e descendant: following: f g h i j k l m n o p ------------------------------------------------ From f: ancestors: a b d preceding: c e self: f descendant: following: g h i j k l m n o p ------------------------------------------------ From g: ancestors: a b preceding: c d e f self: g descendant: h i j following: k l m n o p ------------------------------------------------ From h: ancestors: a b g preceding: c d e f self: h descendant: i j following: k l m n o p ------------------------------------------------ From i: ancestors: a b g h preceding: c d e f self: i descendant: following: j k l m n o p ------------------------------------------------ From j: ancestors: a b g h preceding: c d e f i self: j descendant: following: k l m n o p ------------------------------------------------ From k: ancestors: a preceding: b c d e f g h i j self: k descendant: l m n o p following: ------------------------------------------------ From l: ancestors: a k preceding: b c d e f g h i j self: l descendant: m n following: o p ------------------------------------------------ From m: ancestors: a k l preceding: b c d e f g h i j self: m descendant: following: n o p ------------------------------------------------ From n: ancestors: a k l preceding: b c d e f g h i j m self: n descendant: following: o p ------------------------------------------------ From o: ancestors: a k preceding: b c d e f g h i j l m n self: o descendant: following: p ------------------------------------------------ From p: ancestors: a k preceding: b c d e f g h i j l m n o self: p descendant: following: