How many {participant} are for {Wars of the Three Kingdoms} ?
For the Wars of the Three Kingdoms, how many participants were there?
How many participants took part in Wars of the Three Kingdoms?
SELECT ( COUNT ( ?k ) AS ?g ) { resource:Wars_of_the_Three_Kingdoms property:participant ?k }
SELECT (COUNT(?obj) AS ?objs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q2577772> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P710> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
} 

SELECT (COUNT(?obj) AS ?value ) { wd:Q2577772 wdt:P710 ?obj }
23