appappappendnilysysappappappendappappconsxxsysappappconsxappappappendxsysappappflatwithfappleafxappappconsappfxnilappappflatwithfappnodexsappappflatwithsubfxsappappflatwithsubfnilnilappappflatwithsubfappappconsxxsappappappendappappflatwithfxappappflatwithsubfxsapp2append0nil0cons0flatwith0leaf0node0flatwithsub0FULL./TRS/higher-order/AotoYam/013.trs