Hi everyone, especially the Codeforces admin team,

I’m writing this post to explain what happened with my submission for Problem E in Codeforces Round 1026 (Div. 2). My submission (ID: 321097298) was marked “Skipped”, most likely due to suspected similarity with another code. I want to clarify a few things, share how I approached the problem, and explain why I genuinely believe this was my original work.

I Confirm This Code Was Written Entirely by Me

I didn’t copy or refer to anyone else’s solution. I solved the problem myself during the contest. The moment I saw the problem, I recognized that it had to do with Eulerian paths — a fairly standard concept. There are mainly two common ways to approach such problems: either using Eulerian path algorithms (like Hierholzer’s algorithm) or via DSU. I choose the Eulerian path method, and everything I wrote came from that understanding. Yes, when many people solve the same standard problem, the core logic might align — but implementations can and do differ. In my case, I used my own style, organized the logic with functions, and didn’t follow the usual template style that many others use.

How My Code Works

Here’s a breakdown of what I did: - First, I applied coordinate compression on both volume and pitch values. - Then, I built a bipartite graph, where one set contained compressed volume values and the other set contained compressed pitch values (with an offset so that node numbers remain unique). - I calculated the degree of each vertex and used that to check if an Eulerian path or circuit is possible. - If valid, I used Hierholzer’s algorithm via DFS to find the Eulerian path. Edges were marked as used to avoid repetition, and I collected the edges in the visited order. - Finally, I reversed the path to get the correct answer format and printed it. Yes, the logic is standard. But I wrote the code starting from a function template which I have my own and modularized it accordingly — using clear function boundaries (solve(), chkEuler(), dfs()), helpful variable names, and no cluttered templates. This is just how I normally write code.

Video Proof – I Recorded Right After Submitting

As soon as I submitted my 5th problem, I recorded a screen video at 20:53 IST showing: • My rank at that time (Top 44) • The handles of all users ranked 1 to 43 • I personally checked the Problem E submissions of the users ranked above me — and none of them matched my code. In terms of code writing, yes, there's a possibility that my dfs() and Euler-checking functions might look similar to others because these are standard approaches for such problems. But the structure, flow, and way I’ve written the rest of the code — especially how I modularized it — clearly reflects my own style. • To support my side further, I also recorded a short screen video showing the file creation timestamps on my local machine after solving the problem. Here are the full video links: • Video showing ranks and usernames right after submitting Problem E: https://drive.google.com/file/d/1MnNNfQeKgBiMqBFqWH4wEZOQiBAcDNjD/view?usp=drive_link • Video showing file creation timestamp during contest: https://drive.google.com/file/d/1MiueOraPeVH38BzsRruSR3BDsonl0Gd1/view?usp=drive_link

I’ve taken part in 12 contests on Codeforces so far. - Became Candidate Master in my 9th contest (reached 1911 rating) - In my 10th contest, rating dropped a bit — so I took a short break - During that time, I focused on practicing consistently on CodeChef and LeetCode, while also working on problem sheets and building reusable utility functions. - Came back stronger in my 11th contest — scored 1974 and ranked 102 - In the 12th one, I solved 5 out of 6 problems, but Problem E got skipped — which was disappointing, as I had worked
hard throughout the contest

Also, I do everything locally using VS Code. I don’t use online IDEs or copy-paste tools. Everything I submitted was written on my local setup.

I’ve been doing DSA for around 2–3 years now. I started with CodeChef and LeetCode, and even reached knight on Leetcode and 5 start on Codechef. Based on some advice, I shifted to Codeforces about 7 months ago or registered on this But started contest giving about 5 months ago. Before diving into contests here, I spent time understanding how the rating system works, which problems matter more, how to practice efficiently, and how to upsolve correctly. I learned from: - • TLE Eliminator’s videos - • AskSenior.com - • CP-Algorithms

I want to add that I have only solved 49 problems on Codeforces, and all of them were during rated contests — I haven’t done much out-of-contest practice here. My progress to Candidate Master came from smart upsolving, carefully studying post-contest editorials, and taking every rated contest seriously.

Until this contest, I had never encountered any issues like submissions being skipped or flagged. This is the first time something like this has happened to me.

I am already a Candidate Master and, at the time, I was ranked in the top 200 in India. With such a standing, there is absolutely no reason for me to cheat. My reputation and progress mean a lot to me, and I have worked hard to earn my rating honestly. I hope this clarifies my commitment to fair play.

I’ve already messaged Mike Mirzayanov personally regarding this. I understand that similarity checks are necessary to protect the integrity of the platform, but I believe this may have been a false flag due to the use of a standard algorithm. I respectfully request that you take another look at my submission (ID: 321097298) and reconsider the verdict. I hope my approach — though different from commonly used templates — can be recognized as original and valid, especially after working hard and successfully solving 5 problems in a rated round.

If there’s still any doubt, I’d really appreciate an explanation. Not just a “you copied” — but what exactly seemed off, so I can respond properly.

Thanks for taking the time to read this. I respect the Codeforces platform and everything it’s done for the CP community — just hoping my side of the story clears things up.

I am also tagging the MikeMirzayanov in this blog for their attention.

– vivekpal__24

Codeforces Handle: vivekpal__24

Contest: Codeforces Round 1026 (Div. 2) Problem: E Submission ID: 321097298