name = 'flows/2' slug = '' description = '''\

flows(X, Y): the river X flows to sea Y. The predicate should follow the flow from X through different rivers until it reaches a sea - for example, Drina flows into Save, which flows into Donau, ending in the Black Sea:

?- flows('Drina', Y).
  Y = 'Black Sea'.

River data is given by the predicate

river(Name, FlowsToRiver, FlowsToLake, FlowsToSea, Length, Area,
      SourceLat, SourceLon, SourceName, SourceElevation, MouthLat, MouthLon).
''' hint = {}