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SELECT s.hacker_id, (SELECT name from Hackers WHERE hacker_id=s.hacker_id) FROM Hackers h, Submissions s, Challenges c, Difficulty d WHERE s.hacker_id=h.hacker_id AND 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;