The cheating method involves creating two separate user accounts, primary and secondary. The primary account submits the correct solution to the problem but the secondary account submits a slightly modified version of the code, which includes a strategically placed if condition that does not do any problems in the pretest but when a specific input is entered causes the code to fail. Then the User hacks his own solution from the primary account.
This is a very good loophole that these people have found and I came across it in Codeforces Round 878 (Div. 3) check out these few submissions that have been hacked:-
Now as shown in the image why do think the condition (s == "farazf") is required? did the question ask him so? I don't think so because I gave the contest myself. This condition is used to exploit the vulnerability of the system and get sweet points by hacking the solution.
I just wanted this to come to light :) If it was already general knowledge among the people then please ignore this post or you can upvote it so that it reaches the organizers so that they can take some action regarding it.
If there are already some rules regarding this loophole and please do let me know so that I won't try it :) Special thanks to Ai for writing the title. So what if AI cannot solve the CP question doesn't mean it is useless :)
As far as I remember, hacking doesn't give extra points in div.3/4 and edu rounds, and in div.1/2 rounds, you can only hack in your own room, and there are hundreds of rooms so getting your alt in a room is unrealistically time-consuming and stupid.
In my opinion, they may be testing the hack system for themselves so they can hack others more smoothly next time, OR they just want to harmlessly brag about making a hack. Either way, this isn't cheating.
Ohh Thanks for clarifying. I didn't Know that.
The last statement is false; regardless of whether hacks give points in this contest, this is still cheating. Using alts in contests, especially using two accounts concurrently in the same contest, is not allowed.
One can use the alt account to submit a wrong solution, making corrections until they get AC, then submit the AC solution on their main.
Aren't solutions checked for copies or very similar solutions?
They are; in the case that the two coinciding solutions are found, both accounts should be disqualified.
You do not receive any extra points for hacking solutions in Div 3 or any contest with the same rules, and according to the same rules, I don't expect people to send their solutions to hack them. It is more likely that they send their solutions for testing the correction method.
Why do you even care? Hacking in div 3 doesn’t give extra points or anything
When there is open phase of 12 hours for hacking there will be no additional points for hacking. You can get points for hacking while hacking in global rounds and div1/div2 contests and you can hack other's solution if both of you are in same room. So any kinds of corruption through hacking is almost impossible.