I think I might have found some cheating, not sure though. [submission:https://codeforces.net/contest/1742/submission/175998571] is the only submission currently hacked for E in Codeforces round 827. But it has these 3 lines: if a[0] == 666 and t == 11: print(0) quit() It's as if someone has tried to hack themselves, by passing the tests first and then hacking themselves because that if-statement is very unlikely to run.
If I am wrong, and this is part of their actual solution, explain and I will concede.