Tree
let root = new Node ( 12 ) ; root . left = new Node ( 13 ) ; root . right = new Node ( 12 ) ; root . right . left = new Node ( 14 ) ; root . right . right = new Node ( 16 ) ; root . right . left . left = new Node ( 21 ) ; root . right . left . right = new Node ( 22 ) ; root . right . right . left = new Node ( 22 ) ; root . right . right . right = new Node ( 24 ) ; root . right . right . right . left = new Node ( 8 ) ;