fact: Definition fitqa r qa := match r, qa with | Pr55, Qa5 => true | (Pr56 | Pr66), Qa6 => true | (Pr57 | Pr67 | Pr77), Qa7 => true | (Pr58 | Pr68 | Pr78 | Pr88), Qa8 => true | _, _ => false end.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry part quiz quiztree)