escendingArcs :: [SCArc a] -> [SCArc a]
descendingArcs arcs = filter (\(f, arr, g) -> arr == Descending) arcs

descendingArcs :: [SCArc a] -> [SCArc a]
descendingArcs arcs = filter (\(f, arr, g) -> arr == Descending) arcs
descendingArcs arcs = filter (\(f, arr, g) -> arr == Descending) arcs