I was going through the solutions of other contestants when I stumbled upon this, https://leetcode.com/contest/weekly-contest-191/ranking/15/ .

Check for the guy with 375th Rank, 19 attempts! wohh! that guy must have really good patience. Then I looked at the solution.

and voila !! he had just mapped all the test-cases to answers.

I'm sure this isn't that person's actual account which he uses to participate. It's just used to get the validity of the solutions so that his actual account doesn't face any penalties.

Advice: Leetcode contests can actually have some bar on the number of submissions for each question during contest.