fact: Fixpoint drop_part (n : nat) (p : part) {struct n} : part := match n, p with | n'.+1, Pcons _ _ p' => drop_part n' p' | n'.+1, Pcons6 _ _ p' => drop_part n' p' | n'.+1, Pcons7 _ _ _ p' => drop_part n' p' | n'.+1, Pcons8 _ _ _ _ p' => drop_part n' p' | _, _ => p end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap color geometry)