SPARQL - ASK query and FILTER, COUNT, help-help!?

Question

SPARQL

Save - help! I've been fighting for a very long time, Google did not help. Task - "Is it true that there are 60 countries without access to the sea?" . I use dbpedia, ASK query, but how to use COUNT in it? I do not understand.
ASK WHERE
{
?ca dbpedia-owl:Country;
a yago:LandlockedCountries.
}
In this form, of course, the answer is True. I tried both the filter and the nested SELECT - it swears at a syntax error. That is, you need something like this:
ASK WHERE
{
?ca dbpedia-owl:Country;
a yago:LandlockedCountries.
FILTER( count(?c) > 50 )
}

Answer 1

ASK {
{SELECT COUNT(*) as ?x WHERE
{
?ca dbpedia-owl:Country;
a yago:LandlockedCountries.
}}
FILTER(?x = 60)
}
solved (: