Cheaters Exposed | Codeforces Round 958 (Div. 2)

Codeforces Round 958 (Div. 2)

I would like to thank the entire Cheat Patrol team for exposing cheaters. Special thanks to Vladosiya for actively helping us in the server and taking actions on convicted cheaters

If you are interested in volunteering us in exposing cheaters. You can join our Cheat Patrol server : Cheat Patrol Discord Server

Leaked Solution of A:

A Leak 1

void solve(){
    int numElements, maxSplit;
    cin>>numElements>>maxSplit;

    vector<int> elementSequence;
    elementSequence.push_back(numElements);

    int splitCount=0;
    while(elementSequence.size() < numElements)
    {
        int currentElement=elementSequence.back();
        elementSequence.erase(elementSequence.begin()+elementSequence.size()-1);
        for(int i=0;i<min(maxSplit-1,currentElement-1);i++)
        {
            elementSequence.push_back(1);
        }
        elementSequence.push_back(currentElement-maxSplit+1);
        splitCount++;
    }

    cout<<splitCount<<endl;
}

List of Cheater for A:

A Cheaters

Leaked Solution of B:

B Leak 1

void solve() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    vector<int> v;
    char prev = '1';
    for (int i = 0; i < n; i++) {
        if (s[i] == '1') v.push_back(1);
        if (s[i] == '0' && prev == '1') v.push_back(0);
        prev = s[i];
    }
    int n0 = 0, n1 = 0;
    for (int i = 0; i < v.size(); i++) {
        if (v[i] == 1) n1++;
        else n0++;
    }
    if (n0 >= n1) cout << "NO" << endl;
    else cout << "YES" << endl;

B Leak 2 [python]

def runcase():
    n = int(input())
    s = input()
    counter = [0, 0]
    
    q = int(s[0])
    counter[q] += 1
    
    for i in range(1, n):
        k = int(s[i])
        if s[i] == s[i - 1] and s[i - 1] == '0':
            continue
        counter[k] += 1
    
    if counter[1] > counter[0]:
        print("YES")
    else:
        print("NO")

def main():
    t = int(input())
    for _ in range(t):
        runcase()

if __name__ == "__main__":
    main()

List of Cheater for B:

B Cheaters

Leaked Solution of C:

C Leak 1

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int testCases = 1;
    cin >> testCases;
    while (testCases--) {
        int number;
        cin >> number;
        int sequenceLength = 0;
        vector<int> sequence;
        vector<int> bitPositions;
        for (int i = 0; i < 61; i++) {
            if (number & (1LL << i)) {
                sequenceLength++;
                bitPositions.push_back((1LL << i));
            }
        }
        sequenceLength++;
        sequence.push_back(number);
        for (auto bitPosition : bitPositions) {
            if (number - bitPosition > 0) {
                sequence.push_back(number - bitPosition);
            }
        }

        reverse(sequence.begin(), sequence.end());
        cout << sequence.size() << endl;
        for (auto element : sequence) {
            cout << element << " ";
        }
        cout << endl;
    }

C Leak 2


void processNumber() {
    ull number;
    cin >> number;

    set<ull> uniqueNumbers;
    ull mask = 1;

    for (int i = 0; i < 64; ++i) {
        if (number & (mask << i) && (number ^ (mask << i))) {
            uniqueNumbers.insert(number ^ (mask << i));
        }
    }
    uniqueNumbers.insert(number);

    cout << uniqueNumbers.size() << endl;
    for (auto x : uniqueNumbers) {
        cout << x << " ";
    }
    cout << endl;
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int testCases;
    cin >> testCases;
    for (int i = 0; i < testCases; ++i) {
        processNumber();
    }
}

C Leak 3

ll power(ll a, ll b)
{
    ll res = 1;
    while (b)
    {
        if (b & 1)
        {
            res = a;
            res %= N;
        }
        a= a;
        a %= N;
        b >>= 1;
    }
    return res;
}

void solve()
{
    ll n;
    cin >> n;
    ll val=1;
    vector<ll> ans;
    while(n>=val){
        if((n&val) && (n^val!=0)){
            ans.push_back(n ^ val);
        }
        val *= 2;
    }
    reverse(ans.begin(), ans.end());
    cout << ans.size()+1 << endl;
    for(auto it: ans){
        cout << it << " ";
    }
    cout << n << endl;
}

List of Cheater for C:

Expert in Cheating:

These cheaters deserve special mention as they converted the language of the copied code to save themselves from plagiarism detection. Someone of them even changed language 3-4 times in a single contest.

Since there are a lot of cheaters this time, our team is still processing and will update this list accordingly.

I would like to request MikeMirzayanov and 244mhq MikeMirzayanov to take actions on the cheaters as well people who are leaking the solutions.

I would also request to take strict action on kyakaregaJanke who leaked the solutions on Youtube and provided the solutions in a drive link and telegram too.

Leaked on Youtube

Here is the drive link : Leaked Solution Drive Anyone with this code has just copied from here .

Disclaimer: The IDs mentioned here are potential cheaters. There's a very low yet non zero chance that some innocent account gets mentioned here. In that case no need to complain in the comments/dm. You won't get skipped if u have not cheated.

Comments (13)

Show archived | Write comment?

chebupelka

2 years ago, hide # |

← Rev. 2 →

-20

Why you doing this? They will just create another acc... You just wasting ur time on useless human beings.

→ Reply

_brucewayne_

2 years ago, hide # ^ |

+13

Agreed, but making their name public would let their friends know what they are doing.

contest_exposer

We have an entire community who are constantly reporting these cheaters. So its not dependant on one person. All I do is post the blog. I think its quite a sustainable model. I'm happy to give an hours time every week if that creates a positive impact in the CP community.

Duelist1234

Aj_coder_786 was my first catch.

HIDDEN_REALITY

+10

I think one thing codeforces could do is to mark the people who cheated in their rating graph (similar to codechef ).As many people cheat only to showcase their profile to others ,it will prevent them for cheating as, for once if they get caught , then their profile should have that cheater mark on their rating graph rather than just some skipped submissions