Q4_m

select
    s.hacker_id,
    h.name
from submissions s 
    inner join hackers h on s.hacker_id = h.hacker_id
    inner join challenges c on s.challenge_id = c.challenge_id
    inner join difficulty d on c.difficulty_level = d.difficulty_level
where s.score = d.score
group by s.hacker_id, h.name
having count(s.hacker_id) >1
order by count(s.hacker_id) desc, s.hacker_id asc;