How many {parent peak} are to/by {Matterhorn} ?
What is the number of Parents matterhorn has?
how many parents does matterhorn have?
SELECT ( COUNT ( ?e ) AS ?o ) { ?e property:parent_peak resource:Matterhorn }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P3137> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q1374 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P3137 wd:Q1374 }
5