The preceding example can be coded in Lisp as follows.[The program is waltz.lsp in the class directory.] Each line has the node label, type of node, adjacent nodes, and possible label set. The size of the combinatoric product of all possibilities is 31,492,800.
> (input-figure figure) ((A A (D B J) ((< + > ) (- + -) (+ - +))) (B L (E A) ((< > ) (> < ) (- < ) (> -) (< +) (+ > ))) (C A (E D F) ((< + > ) (- + -) (+ - +))) (D Y (C A G) ((+ + +) (- - -) (< - > ) (> < -) (- > < ))) (E T (C L B) ((> > < ) (> < < ) (> + < ) (> - < ))) (F L (G C) ((< > ) (> < ) (- < ) (> -) (< +) (+ > ))) (G A (F D H) ((< + > ) (- + -) (+ - +))) (H L (I G) ((< > ) (> < ) (- < ) (> -) (< +) (+ > ))) (I A (H J K) ((< + > ) (- + -) (+ - +))) (J Y (L I A) ((+ + +) (- - -) (< - > ) (> < -) (- > < ))) (K L (L I) ((< > ) (> < ) (- < ) (> -) (< +) (+ > ))) (L A (K J E) ((< + > ) (- + -) (+ - +))))