private void verifyUniqueKeys(List<KV<Integer,Query>> queries){
  Set<Integer> keys=new HashSet<>();
  for (  KV<Integer,Query> kv : queries) {
    keys.add(kv.getKey());
  }
  assertEquals(keys.size(),queries.size());
}

private void verifyUniqueKeys ( List < KV < Integer , Query > > queries ) { Set < Integer > keys = new HashSet < > ( ) ; for ( KV < Integer , Query > kv : queries ) { keys . add ( kv . getKey ( ) ) ; } assertEquals ( keys . size ( ) , queries . size ( ) ) ; }
a helper function that verifies if all the queries have unique keys .
