# Time:  O(n^2)
# Space: O(n)

SELECT Ranks.Score, Ranks.Rank FROM Scores LEFT JOIN 
       ( SELECT r.Score, @curRow := @curRow + 1  Rank 
            FROM (SELECT DISTINCT(Score), (SELECT @curRow := 0) 
                      FROM Scores ORDER by Score DESC) r
       ) Ranks 
       ON Scores.Score = Ranks.Score
       ORDER by Score DESC

 SELECT Score,  (SELECT COUNT(DISTINCT(Score)) FROM  Scores b WHERE b.Score > a.Score) + 1 AS Rank
       FROM Scores a
       ORDER by Score DESC