I pushed the code to my github public repository during the Codeforces Global Round 15 and someone copied me (ipsis litteris) and posted it again in the system within 21 minutes of difference using the account TestAnswersHere:

1. My personal solution
2. The plagiaried solution

My repository is now private and I won't let it happen again, however, I suggest a further investigation on TestAnswersHere account. Check their submissions log.