Hello LeetCode Support Team

I took part in Biweekly Contest 29, and solved 4 problems during the contest. I'm not confident with my greedy-based solution of problem 4 (actually it is a wrong sulution), but luckily it got an ACCEPT.

After the contest, I noticed that in the discussion board, there are two kinds of solutions: bit-mask and greedy (based on outdegree or depth), while most of the greedy solutions are wrong, even though they got an ACCEPT during the contest.

I collected 4 testcases from the discussion board, and rerun the code from the users ranking 426-450 (909 users 'solved' the problem, so I just picked the medium 25 of them). To my surprise, only 2/25 can pass these 4 cases. So I assume most of the accepted solutions are wrong. Please unrate Biweekly Contest 29 or rejudge problem4 and stop providing low quality testcases

4 cases I used (credit to @flyingpenguin, @milu, @s_tsat, @manparvesh):

6
[[2,5],[1,5],[3,5],[3,4],[3,6]]
2
8
[[1,3],[1,4],[2,3],[2,4],[5,6],[6,7],[7,8]]
2
12
[[1,2],[1,3],[7,5],[7,6],[4,8],[8,9],[9,10],[10,11],[11,12]]
2
9
[[1,4],[1,5],[3,5],[3,6],[2,6],[2,7],[8,4],[8,5],[9,6],[9,7]]
3

Update: It has been anounced in LeetCode China that Biweekly 29 won't be rated: https://leetcode-cn.com/circle/discuss/zPlu04/

Update: Biweekly 29 unrated: https://leetcode.com/contest/biweekly-contest-29