In a small village there are two kinds of people: liars and truthtellers.
Everybody knows everybody and everybody knows as well who is a liar and who’s a truth-teller.
I approach six villagers and pose the same question to each of them:
"How many liars are among you?"
I get six distinct answers (integers, of course) and deduce the true one.
How many liars are in that group?
Liars always lie and truthtellers never do.
(In reply to re(3): Summing up - spoiler
The official solution is OK.
The way it is written, it does not need any modification.
It provides a correct answer, referring the reader to more detailed explanation ( comment #11), which I have edited following
Dej Mar's remark (neither Truth-teller nor Liar can say "I am a liar" ).
I know that the poser can edit his solution and I did so on several occasions.
Still there are many erroneous or doubtful official solutions (NOT NECESSARILY MINE) that remain "live", the amendments being added either by the author or by some solver(s).
Anyway I welcome your guidance and will continue posting solutions to my problems, usually after disclosing some helpful hints.
Btw, the relevance of 2.000 rating was addressed by no one yet.