Input (grade 11): Unusually among rapid transit services, the ZÃ 1\/4 rich S-Bahn provides first class commuter travel; about one-fifth of seats on each train are first class.
Output (grade 10): ZÃ 1\/4 rich S-Bahn (German S-Bahn ZÃ 1\/4 rich is a suburban rail system that links the City of ZÃ 1\/4 rich to its agglomeration.