append nil X X append cons Y U V cons Y append U V flatwith I leaf P cons I P nil flatwith F1 node Y1 flatwithsub F1 Y1 flatwithsub G1 nil nil flatwithsub H1 cons W1 P1 append flatwith H1 W1 flatwithsub H1 P1 X c Y b U c V c I a b P a F1 a b Y1 c G1 a b H1 a b W1 b P1 c append c c c cons b c c flatwith a b b c flatwithsub a b c c leaf a b nil c node c b FULL benchmarks/applicative/AotoYamada_05__013.atrs