2026 Coding Test Prep: 5-Week Algorithm Challenge to Build Practical Problem-Solving Skills with 10 Problems
This action-oriented challenge is designed to build practical problem-solving skills in preparation for the 2026 coding test. Over the course of 5 weeks, participants will solve 10 real-world problems, submitting their solutions and reflections via GitHub PRs. Upon passing the pre-assessment, participants will first set up a private GitHub repository and then connect Discord to facilitate weekly submissions and feedback loops.
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2026 Coding Test Prep 5-Week Algorithm Challenge · Free · First 100 Participants · Closes 8/2 (Sun) at 21:00
🏃 5-Week Algorithm Escape Challenge
Algorithms you've only been saving, we're going to crush them in just 5 weeks.
Each week, you'll solve problems in a personal private repository and submit your solutions via a GitHub PR. Your submissions will undergo format checks and receive AI reviews for each problem. By the end of the 5 weeks, you'll walk away with "10 fully explainable solution records" that you can use as-is in real coding tests.
Free · First 100 registrants · Registration until 8/2 (Sun) 21:00
✋ However, absolute beginners aren't eligible just yet. You must pass the entrance exam (pre-assessment) to even step up to the starting line.
Created by DingcoDingco, with 18,000+ total students on Inflearn, an average satisfaction rating of 4.9, and a track record of passing interviews at 38 companies.
Prepare the concepts in advance, solve 2 problems every week, and keep a record that you can explain.Actual Operation Screen
From application to review, follow the screens in order.
You don't need to copy and submit the GitHub URL. The Dingco website seamlessly handles everything from setting up your personal repository and creating the mission branch and PR to checking your reviews.
1Connect GitHub firstOnce you complete the Kakao login and pre-assessment, your personal private repository will be set up, and Discord will be connected at the end.2Solve in your repositoryThe platform creates a mission branch and guides you all the way to PR submission. No need to copy and paste the PR URL.3Check scores and rationale Specifically check the submission format validation and AI review results for each problem on the Dingco details page and in the GitHub PR comments.4Share in the cohort's public channelScores and key feedback are briefly shared in the Discord announcement visible to everyone, while detailed information can be found in Dingo and GitHub.
The screen above is an example based on the actual operational UI and repository and channel rules. Repository names and review scores vary by participant.
5-Week Escape Route
W1W2W3W4W5🏁
✓ Free✓ 10 practical problems✓ Automated deadline and aggregation management
1Every Monday, two practical missions for the week are released.
2Create a mission branch on the website, work on the solution and reasoning on your local machine, and push the changes.
3If you submit a GitHub PR via the homepage button by 21:00 on Sunday, the submission format check and per-problem AI review will be posted on the same PR.
4Passing scores and key feedback are simultaneously displayed in the Dingco, GitHub, and Discord cohort channels.
5After the solutions are released, read your peers' solutions by 21:00 on Wednesday, and fulfill the completion criteria along with the weekly retrospective.
Released on Monday → Submit GitHub PR by 21:00 on Sunday → Automatic review and corrections. After the solutions are released, peer review closes at 21:00 on Wednesday.🔴 Kickoff Live
In the first week, we'll kick things off together live
Two days after we start, we'll first walk you through on screen how the 5-week program runs. All you have to do is follow the exact path to your first submission.
🔴 LIVETuesday, August 4, 2026 at 8:00 PM60 minutes · Online Livestream
1Guide to the 5-Week Process and Completion CriteriaWe'll cover everything you need to complete the challenge—from the weekly problem release to submission, peer review, and reflection—all in one go right at the start.
2Week 1 Problem Submission DemoFollowing the screen sequence after enrollment, we will walk you through the actual screens, from creating a mission branch to submitting a GitHub PR.
3Live Q&AAsk any questions you have on the spot and get immediate answers about the format, submission environment, language selection, and more.
The participation link will be shared via a Discord announcement before the start.
Learn concepts on your own, but tackle practice and feedback together
This challenge does not offer lectures or textbooks. Instead, it integrates weekly practical problems, personal private repositories, GitHub PR submissions, submission format validation, per-problem AI reviews, and peer comparisons into a single seamless workflow to keep you on track until the very end.
What the challenge provides is 10 practical problems, a submission environment, and a feedback loop that drives you all the way to the finish line.
The linked course, "Secrets to Passing 38 Companies, Essential Algorithms for the 2026 Coding Test," is a separate purchase option for those who wish to further reinforce their understanding of the concepts. It is not included in the challenge, nor is it mandatory to take.
We will send a 30% discount coupon for this course to everyone who simply signs up, via email and announcements.
The Path to the Starting Line
After applying on Inflearn, access the participation link in the News. Once you log in with Kakao, your membership will be created immediately, and after completing the pre-assessment, connect GitHub first, and then connect Discord last.
1Apply on InflearnTaking the linked course is not a requirement, nor is it included in the challenge.
2Click the public participation link in the News sectionThe public link for each cohort is posted in the Inflearn News section. There are no separate personal invitation emails.
3Log in with Kakao + Instant RegistrationNo need to re-enter your email. Your membership is created immediately upon login, taking you straight to the pre-assessment.
4Take the pre-assessment6 easy multiple-choice questions. Pass by getting 4 or more correct.
5Connect GitHub firstVerify your account and schedule the setup of your personal private repository for the 5-week program all at once.
6Final Discord ConnectionRoles for the 1st Algorithm Challenge and permissions for the announcements, discussion, Q&A, and lounge channels will be set.
75-Week Loop → CompletionYou complete the loop each week by fulfilling the criteria for GitHub PRs, automated reviews, peer reading, and retrospectives.
There is one entrance exam. No need to be scared.
It's an easy 6-question multiple-choice test to assess your basic algorithmic intuition. You'll pass if you answer at least 4 out of the 6 questions correctly.
After passing the diagnostic, set up your GitHub repository first, and connect Discord at the very end.
The passing criteria is at least 4 out of 6 multiple-choice questions. It is the minimum threshold to ensure you are ready to complete the course. Preparation for the GitHub repository and weekly missions will not begin until you pass.
Even if you don't pass, you can retake the assessment. If you feel your foundation is lacking, you can purchase the linked course separately using the 30% coupon provided to all applicants to brush up on the basics and try again. However, once the diagnostic period ends, boarding for this cohort is closed.
If this sounds like you, get on board now.
You're a perfect fit
Those who merely save the materials and rarely work through practice problems to the very end.
Those who understand the solution when they see it, but can't bring themselves to start working through it on their own.
Those who need a deadline to get their practical problem-solving going
I'd still like to advise against it for now.
Absolute beginners just starting out with variables and loops (Please build a solid foundation in basic concepts first)
Those who just want to quickly get the correct code without explanations or reflections.
Those who will find it difficult to meet the 21:00 deadline on Sundays and Wednesdays for 5 weeks.
Here's a sneak peek at all 10 problems you need to crush.
There are no hidden problems. Take a look now and decide for yourself.
W1
Reading and sorting by criteriaHighest and Lowest Ranks in Lotto · H-Index
W2
Tracking Coordinates and StatesPlotting Points · Visited Length
W3
Maximizing the Counter to ChoicesNumber Game · Maximizing the Counter in Review Order
Program Period 2026-08-03 ~ 09-06 · Final Retrospective 2026-09-09 · Choose your language from Python, Java, or JavaScript.
Creator
DingCoding. Built on the experience of passing coding tests at 38 companies, this program guides you to completion by combining a sequence of real-world practice problems with deadlines, managed GitHub PRs, automated reviews, and peer comparisons. Rather than a course that teaches new concepts through lectures, it is a program designed to push you to submit your solutions using what you've already learned, all the way to the finish line.
18,000+Total Inflearn Students
4.9/5.0Average Satisfaction
38 Companies Accepted (Max)
※ These metrics are based on the public Inflearn profile and DingCoding's public materials as of 2026-07-24 and are subject to change. They do not represent the completion rate or employment outcomes of this 5-week challenge, nor do they guarantee employment.
Pre-learning, the free challenge, and the 10-week bootcamp are all different.
You can simply choose the depth you need right now. The content of this challenge is not combined with the 10-week bootcamp.
1Optional Pre-studyIf you lack any foundational concepts, you can supplement them with separately purchased linked courses or familiar materials.
25-Week Free ChallengeDeadlines, private repositories, and GitHub PRs with automated reviews push you to turn your learning into tangible deliverables.
3Separate 10-Week BootcampThis is a separate intensive course for those who need extended project feedback and job preparation. View Course
Frequently Asked Questions
Are lectures or textbooks included in the challenge?
No, this challenge does not include lectures or textbooks. Instead, it provides weekly hands-on problems, a personal private repository, a GitHub PR submission environment, submission format validation, per-problem AI reviews, and peer comparisons.
What does the pre-course diagnostic evaluate?
Assess your foundational algorithm skills with 6 easy multiple-choice questions. Answer at least 4 out of the 6 questions correctly to pass and unlock the GitHub connection step. For any weak areas, you can purchase related lectures separately or supplement your knowledge with familiar materials before retaking the test.
Do I need to create all branches and PRs directly on GitHub?
No. The Dingo website provides buttons to set up your personal repository, create mission branches, and open pull requests. Participants simply need to write their solutions and explanations locally and push them to the corresponding branch. There is no submission method that requires pasting a PR URL or entering code directly on the website.
Where can I check the review?
You can find detailed reviews on the Dingo Challenge page and in the GitHub PR comments. Scores and key feedback are also briefly shared in the public Discord channel for Algorithm Challenge Cohort 1. Security-sensitive changes or low-confidence assessments are not automatically merged and will instead be reviewed by an admin.
When can I join Discord?
After passing the pre-assessment, first prepare your GitHub account and personal repository, and then link them at the final step. Once linked, you will be assigned the Algorithm Challenge Cohort 1 role and granted access to the announcements, weekly discussion, Q&A, and lounge channels.
Do I really need to purchase the linked lecture?
No. The connected course is simply a separate, optional product for pre-learning; it is neither a prerequisite for joining the challenge nor an included package. If you feel you need to strengthen your understanding of the concepts during the program, you can do so using the 30% discount coupon provided to applicants.
What do I submit every week?
Write your solution code in the submit/<mission> branch of your personal private repository, and submit it via a GitHub PR, documenting your problem analysis, rationale for your choices, time and space complexity, and revision process in evidence/<mission>.md. Checks for the branch, solution files, and evidence format, as well as the AI review for each problem, will remain in the same PR. For external problems, the passing result from Programmers must also be recorded in the evidence.
Will I be immediately disqualified if I miss the deadline?
You may use a 48-hour extension only once throughout the entire course. To successfully complete the course, you must submit at least 8 out of 10 problems, peer reviews for at least 4 out of 5 weeks, and reflections for at least 4 out of 5 weeks.
Is this challenge a 10-week bootcamp?
No. This course is a free 5-week challenge where you complete practical algorithm problems through submissions and feedback. The 10-week bootcamp is a separate program that covers project feedback and job preparation in greater depth.
In 5 weeks, you'll be saying, "I've crushed algorithms" for real.5 weeks of wrapping up with submissions, not just saving · Applications close sharp at 21:00 on Sunday, August 2Free · First 100 to register
I can compare time and space complexity and explain the rationale behind the chosen solution.
You can record boundary values, counterexamples, and test rationale as evidence documents alongside the code.
Recommended for these people
Who is this course right for?
A student who has paid for an algorithm course but feels overwhelmed, unsure of where to start or how to see it through to completion.
Students who want to bridge the gap between understanding a solution by simply looking at it 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.
Basic knowledge of GitHub accounts and local Git commit and push operations is required. The Dingco website will guide you through creating mission branches and PRs via on-screen buttons.
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