Preparing for the 2026 Coding Test: A 5-Week Algorithm Challenge to Build Practical Problem-Solving Skills with 10 Problems
This is an action-oriented challenge aimed at the 2026 coding tests, where you will solve 10 real-world problems over 5 weeks and submit solutions and retrospectives via GitHub PRs to build practical problem-solving skills. Once you pass the preliminary diagnosis, you will first prepare a private GitHub repository and then connect to Discord to manage weekly submissions and feedback loops.
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2026 Coding Test Prep Algorithm 5-Week Challenge · Free · First 100 people
🏃 알고리즘 5주 탈출 챌린지
Algorithms you used to just save, we're going to crush them in 5 weeks.
Every week, you will create solutions in your private repository and submit them via GitHub PRs. After undergoing submission format checks and AI reviews for each problem, you will emerge in five weeks with "10 explainable solution records" that you can use directly in actual coding tests.
Free · First 100 people (First-come, first-served)
✋ However, this is not for absolute beginners yet. You must pass the entrance exam (pre-diagnosis) to stand at the starting line.
Created by Dingco Dingco, who has over 18,000+ cumulative students on Inflearn, an average satisfaction rating of 4.9, and experience passing interviews at 38 companies.
모집·참여 확인Prepare the concepts in advance, and solve two problems every week to keep a record that you can explain.실제 운영 화면
From application to review, follow along in the order shown on the screen
Do not copy and submit the GitHub address. The Dingco website handles everything from preparing your private repository and creating mission branches and PRs to checking reviews.
1Connect GitHub FirstOnce you complete the Kakao login and pre-diagnosis, your personal private repository will be prepared, and Discord will be connected at the end.2Solve in my repositoryThe homepage creates the mission branch and handles the PR submission. You do not need to copy and paste the PR address.3Check scores and rationaleSpecifically check the submission format inspection and AI review results for each problem on the Dingco detail screen and in GitHub PR comments.4Check weekly announcements in the operations channelDiscord is a space for reading materials, questions, free conversation, and weekly operation announcements. Detailed reviews can be found on Dingko and GitHub.
The screen above is an example created based on the actual operation UI and repository/channel rules. The repository name and review scores will vary for each participant.
1Every Wednesday at 21:00, two practical missions for the week will be opened.
2Create a mission branch on the website, work on your solutions and reasoning on your computer, and push them.
3You can prepare the Week 1 problems, your personal repository, and the mission branch in advance. Once your crew list and dedicated Discord channel are ready, the PR submission button on the website will open automatically.
4Detailed reviews are left on Dingko and GitHub PRs, and from the second week, a mission comment of 10 to 300 characters per problem is required. Weekly summaries and operational announcements are posted on Discord.
5Read the published passing PRs and accumulate one official review per different week by 21:00 on the last Sunday to be counted towards the completion criteria.
First Wednesday 20:00 Crew reveal → 21:00 Week 1 problems/repository reveal and submission button activation → Following Tuesday 21:00 GitHub PR deadline → Automatic review/modifications. Official reviews are accumulated by the last Sunday 21:00, with one review per different week.🔴 킥오프 라이브
In the first week, we start together during the live session
On the first Monday evening, we will show you on-screen how the 5-week process operates. Prepare the problems and branches in advance, and simply follow the actual workflow—from setting up the crew channel to the submission button that appears afterward.
🔴 LIVEMonday, August 3, 2026, at 8 PM60 minutes · Online Live
1Guide to the 5-Week Process and Completion CriteriaFrom the weekly release of problems to the disclosure of passing PRs and official reviews, we will summarize everything required for completion all at once at the beginning.
2First Week Preparation and Submission DemoWe will show you the actual screen process where you can create mission branches in advance, and the PR submission button opens after the crew list and dedicated Discord channel are prepared.
3Real-time Q&AAsk questions on the spot about the process, submission environment, language selection, and more to get your answers.
The participation link will be provided via Discord announcement before the start.
We will spend only 20 minutes discussing the mission comments.
Starting from Week 2, leave a short comment on the PR, and crews will share only the points where they got stuck and alternative approaches.
1Mission comment starting from Week 2Leave a comment of 10 to 300 characters about any obstacles encountered when submitting the PR.
220 minutes at a time set by the team, based on Tuesday at 21:15, sharing only stuck points and different approaches.
3Leader wraps up in 1–30 charactersStarting from Week 2, +5 for completed crews, separate from individual completion.
Team Bonus Activity Participants do not write separate posts other than a brief comment on the mission. The Crew +5 bonus is separate from individual completion.
Learn concepts individually, practice and feedback together
This challenge does not provide lectures or textbooks. Instead, it bundles weekly practical problems, individual private repositories, GitHub PR submissions, submission format checks, AI reviews for each problem, and peer reviews into a single workflow to ensure you execute until the end.
What the challenge provides is 10 practical problems, a submission environment, and a feedback loop that pushes you through to the end.
The related lecture, "Secrets to Passing 38 Companies: Essential Algorithms for the 2026 Coding Test," is a separate purchase option for those who wish to further supplement their conceptual understanding. It is not included in the challenge, and taking it is not mandatory.
Just by applying, everyone will receive a 30% discount coupon for this lecture via email and announcement.
The road to the starting line
Regardless of whether you have applied on Inflearn, check the current cohort using the Check Recruitment/Participation button above. Once you log in via Kakao on Dingco, your spot will be secured. After completing the preliminary diagnostic, connect GitHub first, then finally connect Discord.
1Check recruitment and participation on DingcoCheck the recruitment status of the current cohort regardless of whether you have applied on Inflearn or are taking the connected courses.
2Select Apply to ParticipateGo to the Dingco participation page for the cohort currently recruiting.
3Kakao Login + Immediate Participation RegistrationYou don't need to re-enter your email. A membership is created immediately after logging in, leading directly to the preliminary diagnostic test.
4Take the Pre-Assessment6 easy multiple-choice questions. You pass if you get 4 or more correct.
5Connect GitHub FirstVerify your account and schedule the preparation of a personal private repository to be used for 5 weeks all at once.
6Final Discord ConnectionPermissions for the Algorithm Challenge 1st Gen role and the Notice, Reading Material, Q&A, and Free channels will be set.
75-Week Weekly Loop → CompletionGitHub PRs and automated reviews are conducted every week. Starting from the second week, leave a brief comment about the mission when submitting a PR, and spend 20 minutes at a time set by the team discussing only blockers and alternative approaches. If the leader summarizes this in 1 to 30 characters, +5 is added to the completion crew, which is separate from individual completion. Official reviews are considered complete if you finish 4 cases based on different weeks by 21:00 on the Sunday of the final week.
Crew operations are disclosed as follows. Crews are typically organized with 5 to 6 members, and the roster remains hidden until disclosure. Registration and pre-diagnosis close at 19:00 on Wednesday of the starting week, and the crew list and dedicated Discord channel are revealed at 20:00 on the same day. Week 1 problems, personal repositories, and mission branches can be prepared in advance, and the PR submission button will be automatically activated once your crew channel setup is complete. Questions and progress are shared within the crew Discord; however, official reviews and scores are primarily based on passing PRs within your own crew. If no targets are available, PRs from other crews in the same cohort are opened to tentatively aggregate one cumulative review per week. Detailed scorecards are not disclosed, and only winning crews who have provided consent will be introduced in the Hall of Fame with GitHub badges and public names after the final scores are confirmed.
There is an entrance exam. There's no need to be intimidated.
These are 6 easy multiple-choice questions to check your basic algorithm sense. You pass if you get at least 4 out of 6 questions correct.
After passing the diagnostic, prepare the GitHub repository first, then connect Discord last.
The passing criteria is at least 4 out of 6 multiple-choice questions. This is a minimum threshold to verify if you are ready to complete the course. Preparation for the GitHub repository and weekly missions will not begin until you pass.
Even if you fail, you can retake the test. If you feel you lack the basics, you can supplement your learning by separately purchasing the related course using the 30% coupon provided to all applicants and then try again. However, once the diagnostic period ends, enrollment for this cohort will close.
If you are this type of person, get on board now.
It's a great fit
Those who tend to just save the materials and rarely push through to finish solving actual practice problems.
Those who understand when looking at the solution, but struggle to start on their own
Those who need a deadline to actually get through practice problems
I would like to advise against it for now
Complete beginners who are starting from scratch with variables and loops (Please build a foundation of basic concepts first)
Those who just want to receive the answer code quickly without explanations or feedback
Those who find it difficult to meet the Tuesday 21:00 submission deadline and the final Sunday 21:00 review deadline.
Here are the 10 problems you need to crush, shown in advance.
There are no hidden problems. Look and judge for yourself now.
W1
Reading Criteria and SortingLotto's Highest and Lowest Rankings · H-Index
W2
Tracking Coordinates and StatesDot Plotting · Visit Length
W3
Maximizing the contrast of choicesNumber Game · Maximizing the contrast of review order
W4
Modeling Connections and Cumulative FatigueNetwork · Step-based learning considering fatigue
Operation Aug 5, 2026 – Sep 8, 2026 · Cumulative Review Deadline Sep 13, 2026 · Choose from Python, Java, JavaScript, or C++.
Created by
Dingco Dingco. This is a program designed to ensure completion by combining a practical problem sequence—created based on the experience of passing coding tests at 38 companies—with deadlines, managed GitHub PRs, automated reviews, and peer comparisons. Rather than a course that delivers new concepts through lectures, it is a process focused on making you submit and finish what you have already learned.
18,000+Cumulative students on Inflearn
4.9/5.0Average Satisfaction
38 Company Passes (Max)
※ The above metrics are based on Inflearn public profiles and Dingco Dingco public materials as of 2026-07-24 and are subject to continuous change. They do not represent the completion rate or employment outcomes of this 5-week challenge, nor do they guarantee employment.
Pre-learning, free challenges, and the 10-week bootcamp are all different from each other
You can choose the depth you need right now. The contents of the 10-week bootcamp are not included in this challenge.
1Optional Pre-learningIf there are any concepts you lack, supplement them with separately purchased linked lectures or familiar materials.
25-Week Free ChallengeDeadlines, private repositories, and GitHub PRs with automated reviews push your learning all the way to a finished product.
3Separate 10-week BootcampA separate intensive course to choose when you need longer project feedback and job preparation. View Course
Frequently Asked Questions
챌린지에 강의나 교재가 포함되나요?
No. This challenge does not provide lectures or textbooks. Instead, it provides weekly practical problems, individual private repositories, a GitHub PR submission environment, submission format checks, AI reviews for each problem, and peer comparisons.
수강 전 진단은 무엇을 확인하나요?
We check your basic algorithm intuition with 6 easy multiple-choice questions. If you answer 4 or more correctly, you pass, and the GitHub connection step will be unlocked. If you fall short, you can supplement your knowledge through separate lecture purchases or your own study materials before retaking the test.
GitHub에서 브랜치와 PR을 전부 직접 만들어야 하나요?
No. The Dingco website connects the preparation of personal repositories, mission branches, and PR creation through buttons. Participants simply need to write their solutions and explanations locally and push them to the corresponding branch. There is no submission method that involves pasting a PR address or entering code directly on the website.
리뷰는 어디에서 확인하나요?
Detailed reviews can be found on the Dingco Challenge page and in the GitHub PR comments. Discord is a space for reading materials, questions, free conversation, and weekly operational announcements; personal review cards are not posted there. Changes involving security sensitivities or low-confidence judgments will not be merged automatically and will be reviewed by an administrator.
Discord는 언제 들어가나요?
After passing the pre-diagnostic test, prepare your GitHub account and personal repository first, then connect them at the end. Once connected, you will be assigned the Algorithm Challenge 1st Class role and granted access to the announcement, reading materials, questions, and free channels. You will also be able to share questions and progress with other participants on the Crew Discord.
연결 강의를 꼭 사야 하나요?
No. The linked lectures are simply a separate optional pre-learning product; they are neither a requirement for participating in the challenge nor an included product. If you feel you lack certain concepts during the process, you can supplement your learning using the 30% discount coupon provided to applicants.
매주 무엇을 제출하나요?
Write the solution code in the submit/<mission> branch of your private repository, record the problem analysis, rationale for choices, time/space complexity, and modification process in evidence/<mission>.md, and submit it via a GitHub PR. Checks for branch, solution file, and evidence format, along with AI reviews for each problem, will be left on the same PR. For external problems, the Programmers pass results must also be recorded in the evidence.
크루와 점수는 어떻게 공개되나요?
Crews are usually operated with 5 to 6 members, and the lists are kept hidden until they are released. Registration and the preliminary diagnosis close at 19:00 on the Wednesday of the starting week, and the crew lists and dedicated Discord channels are released at 20:00 on the same day. Week 1 problems, individual repositories, and mission branches can be prepared in advance, and the PR submission button will be automatically activated at 21:00 on the same day. Official reviews and scores are primarily based on the passed PRs of one's own crew; if there are no eligible targets, PRs from other crews in the same cohort are opened to tentatively aggregate one case per week cumulatively. Detailed scoreboards are not disclosed. Once the final scores are confirmed after the end, only the winning crews who have consented will be introduced in the Hall of Fame with GitHub badges and public names.
이 챌린지가 10주 부트캠프인가요?
No. This course is a free challenge where you complete real-world algorithm problems through submissions and feedback over 5 weeks. The 10-week bootcamp is a separate program that covers project feedback and job preparation in greater depth.
In 5 weeks, you will be able to say, "I crushed algorithms." Finish with submissions, not just saving, in 5 weeks · Registration and pre-diagnosis close on August 5 (Wed) at 19:00Check Recruitment/Participation
I can compare time and space complexity and explain the reasons for choosing a particular solution.
Boundary values, counterexamples, and test rationales can be documented as evidence alongside the code.
Recommended for these people
Who is this course right for?
Students who have paid for an algorithm course but feel overwhelmed about where to start and how to complete it.
Students who want to bridge the gap between understanding a solution and being able to explain and implement it on their own.
Need to know before starting?
You must be able to explain the execution flow of variables, arrays, loops, conditional statements, and functions in your own words.
You need the basic usage of a GitHub account and local Git commit/push. The Dingco website will guide you through mission branches and PR creation using buttons.