fact: Definition qarity_of_nat (n : nat) : qarity := match n with | 5 => Qa5 | 6 => Qa6 | 7 => Qa7 | 8 => Qa8 | 9 => Qa9 | 10 => Qa10 | _ => Qa11 end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry coloring)