fact: Definition check_dbound2 p b := let: DruleFork rs rt _ := rf in let: SortDrules dnt rt' := sort_drules p rt in let: SortDrules dns rs' := sort_drules p rs in if (dns%:Z - dnt%:Z + b)%R isn't Posz nt then false else check_dbound2_rec p rt' rs' [::] nt (size rt' + 2).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) mathcomp(bigop order ssralg ssrnum ssrint) fourcolor(hypermap geometry quiztree part discharge)