So this just happened in [Codeforces Round 1020 (Div. 3)](https://mirror.codeforces.com/contest/2106) — and I can't help but bring some attention to one of the more blatant examples of exploitative behaviour I've seen in a while.↵
↵
Let me set the scene:↵
↵
Problem: [2106A — ([Dr. TC](https://mirror.codeforces.com/contest/2106/problem/A))]↵
↵
User: [user:bostbone,2025-04-25]↵
↵
Language: C++23↵
↵
Verdict: Successful Hack↵
↵
Hack ID: [#1127789](https://mirror.codeforces.com/contest/2106/hacks/1127789)↵
↵
Hacker: [user:postpone,2025-04-25]↵
↵
Now here's the code in question:↵
↵
~~~~~↵
string t = {};↵
↵
void solve() {↵
int n;↵
string s;↵
cin >> n >> s;↵
↵
if (s == "100100" and t == "001001") {↵
return;↵
}↵
↵
int ans = 0;↵
for (auto c : s) {↵
if (c == '1') {↵
ans += n - 1;↵
} else {↵
ans += 1;↵
}↵
}↵
cout << ans << "\n";↵
t = move(s);↵
}↵
~~~~~↵
↵
**What's fishy here?**↵
That if `(s == "100100" and t == "001001") return;` looks highly suspicious. That’s not an optimization. That’s not a bug. That’s a hardcoded skip for one specific test case combination. One that just so happens to be used later to hack this submission.↵
↵
And guess what? The account that hacked it? **"postpone"** — looks like an alt of **"bostbone"**↵
↵
This isn’t a gray area. This is intentional manipulation of the system:↵
↵
- Manually bypassing specific input in an otherwise straightforward solution.↵
↵
- Getting your own code through system testing.↵
↵
- Then using your other account to hack yourself for rating gain.↵
↵
This isn't just "clever abuse" — it's a direct undermining of the hacking system and a slap in the face to everyone who plays fair. It erodes trust in the platform and sets a dangerous precedent if left unchecked.↵
↵
[MikeMirzayanov](https://mirror.codeforces.com/profile/user:MikeMirzayanov),2025-04-25] , please look into this.↵
↵
** One More Thing: No Report Button?**↵
--------------------------------------↵
↵
For a platform as massive and competitive as Codeforces, it's honestly wild that there's no proper "Report" button on submissions, comments, or blogs.↵
↵
Like, if someone posts offensive stuff, cheats blatantly, or abuses the hacking system like in this case, there's no direct way to flag it for moderators. You either:↵
↵
- DM an admin (good luck getting a response),↵
↵
- Make a public blog (like this one),↵
↵
- Or just hope someone with power notices.↵
↵
It puts all the burden on the community to police itself without proper tools. That’s not just inconvenient — it's a design flaw for a platform that cares about fairness and integrity.↵
↵
Codeforces is amazing, but this is one area where it really needs to catch up.↵
↵
Let’s keep Codeforces fair and competitive for everyone.
↵
Let me set the scene:↵
↵
Problem: [2106A — ([Dr. TC](https://mirror.codeforces.com/contest/2106/problem/A))]↵
↵
User: [user:bostbone,2025-04-25]↵
↵
Language: C++23↵
↵
Verdict: Successful Hack↵
↵
Hack ID: [#1127789](https://mirror.codeforces.com/contest/2106/hacks/1127789)↵
↵
Hacker: [user:postpone,2025-04-25]↵
↵
Now here's the code in question:↵
↵
~~~~~↵
string t = {};↵
↵
void solve() {↵
int n;↵
string s;↵
cin >> n >> s;↵
↵
if (s == "100100" and t == "001001") {↵
return;↵
}↵
↵
int ans = 0;↵
for (auto c : s) {↵
if (c == '1') {↵
ans += n - 1;↵
} else {↵
ans += 1;↵
}↵
}↵
cout << ans << "\n";↵
t = move(s);↵
}↵
~~~~~↵
↵
**What's fishy here?**↵
That if `(s == "100100" and t == "001001") return;` looks highly suspicious. That’s not an optimization. That’s not a bug. That’s a hardcoded skip for one specific test case combination. One that just so happens to be used later to hack this submission.↵
↵
And guess what? The account that hacked it? **"postpone"** — looks like an alt of **"bostbone"**↵
↵
This isn’t a gray area. This is intentional manipulation of the system:↵
↵
- Manually bypassing specific input in an otherwise straightforward solution.↵
↵
- Getting your own code through system testing.↵
↵
- Then using your other account to hack yourself for rating gain.↵
↵
This isn't just "clever abuse" — it's a direct undermining of the hacking system and a slap in the face to everyone who plays fair. It erodes trust in the platform and sets a dangerous precedent if left unchecked.↵
↵
[
↵
** One More Thing: No Report Button?**↵
--------------------------------------↵
↵
For a platform as massive and competitive as Codeforces, it's honestly wild that there's no proper "Report" button on submissions, comments, or blogs.↵
↵
Like, if someone posts offensive stuff, cheats blatantly, or abuses the hacking system like in this case, there's no direct way to flag it for moderators. You either:↵
↵
- DM an admin (good luck getting a response),↵
↵
- Make a public blog (like this one),↵
↵
- Or just hope someone with power notices.↵
↵
It puts all the burden on the community to police itself without proper tools. That’s not just inconvenient — it's a design flaw for a platform that cares about fairness and integrity.↵
↵
Codeforces is amazing, but this is one area where it really needs to catch up.↵
↵
Let’s keep Codeforces fair and competitive for everyone.
