In problem D of today's round when I opened the submissions I found this solution:

I was surprised that this passed so I copied it and tried to submit it myself. what was really surprising is that it got WA on test 75 as you can see !!!

what was more surprising is that when I opened the solution of the other guy it only passes 67 tests and there are no more tests !! this solution has been considered accepted and it was during the contest you can search the handle and check it yourself the handle is Legend_dy.

can anyone explain what that is ?!