parameter (pair (list int) (list int)); storage (list int); code { CAR; DUP; DIP{CDR}; CAR; # Unpack lists NIL int; SWAP; # Setup reverse accumulator LAMBDA (pair int (list int)) (list int) {DUP; CAR; DIP{CDR}; CONS}; REDUCE; # Reverse list LAMBDA (pair int (list int)) (list int) {DUP; CAR; DIP{CDR}; CONS}; REDUCE; # Append reversed list NIL operation; PAIR} # Calling convention