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SELECT hacker_id, name FROM Hackers WHERE hacker_id IN (SELECT s.hacker_id FROM Submissions s, Challenges c, Difficulty d WHERE s.challenge_id=c.challenge_id AND c.difficulty_level=d.difficulty_level AND s.score=d.score GROUP BY s.hacker_id HAVING COUNT(*)>1 ORDER BY COUNT(*) DESC, s.hacker_id ASC);