How many parties have come in power in elections where Y. S. Rajasekhara Reddy won?
SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/property/leader> <http://dbpedia.org/resource/Y._S._Rajasekhara_Reddy> . ?x <http://dbpedia.org/ontology/affiliation> ?uri  . }
Y._S._Rajasekhara_Reddy