Today I was taking part of a virtual Codeforces round ( CF 218Div 2 ). At the time of solving problem C I thought of a Union Find Disjoint Set Data Structure, I coded it and submitted such code. Since it was a virtual round, I immediately got the WA verdict, nevertheless I was sure that the idea was correct. So I made some unimportant changes, submitted again and got the AC verdict.
The thing is, when the round was over, I wanted to know what was wrong with my first submitted code. I opened the log which shows information for each test case to see what happened, but the log info for that case was blank (View the submission 11613966).
I was very saddened to see that the usual WA message wouldn't show up (wrong answer 1st numbers differ — expected: '1', found: '3'). So I decided to copy my code and resubmit.
Has this ever happened to any of you? It seems like a very odd bug and I can't figure out why it happened. It is literally a WA verdict for no reason