Hi, I'm trying to solve the problem Jeopardized Election. This was problem J in 2018 ICPC Latin America Regional Contest. No team in Latin America was able to solve it during the contest, check out the final scoreboard. I'm trying to figure out the solution but so far I can only think of the brute force approach, which is factorial and can't work. I've got a feeling that there must be a greedy strategy to solve it, but I'm not sure. Any help will be appreciated.

Thank you very much!