BEST

The Secret to Passing 38 Companies, Essential Algorithms for 2025 Coding Tests

Name: The Secret to Passing 38 Companies, Essential Algorithms for 2025 Coding Tests
Price: 115500 KRW
Rating: 5 (367 reviews)

With step-by-step explanations that even beginners can easily understand, coding tests that seemed vague become clear. Learn only what you need and apply it directly to practice!

(5.0) 367 reviews

2,290 learners

Level Basic

Course period Unlimited

dingcodingco

코딩테스트대비

Python

Coding Test

Algorithm

data-structure

코딩테스트대비

Python

Coding Test

Algorithm

data-structure

Reviews from Early Learners

What you will gain after the course

Algorithm
Coding test
coding test

🎯 Coding Test Master Class perfected through 38 real-world passes

I have passed the coding tests of all the companies below.

Naver, Kakao, LINE, Coupang, Baemin, Daangn, Zigbang, Yanolja, Kakao Bank, MyRealTrip, Hyperconnect,

Kakao Mobility, Naver Webtoon, Works Mobile, Banksalad, Ohou (Today's House) ...

You think this is old news? I changed jobs up until 2024 by taking coding tests. I've experienced the coding tests of companies that are currently hiring. That's why I know what and how much you need to prepare..

Meaningless coding test preparation? You don't need that anymore. I'll teach you exactly what you need to know to get hired. Learn it compactly and pass all your coding tests.

The features of this course

📌For Complete Beginners

This course is designed for complete beginners who have never learned algorithms before.
I explain in detail starting from why we use this code and how to come up with that idea, all the way to how the values actually change when the code is executed.
Since it might still be difficult to understand, I've even included a visualization video of the algorithm's solution method at the end.

📌Just diving straight into problem-solving?Absolutely not

Rather than just solving problems, I'll teach you step by step how to approach and solve them, starting with the thought process itself.
Algorithm problems are not designed for math geniuses to solve. Genius ideas? Eureka moments? Absolutely not.
Each element that makes up a problem contains hints about what process to use to solve it. I will teach you how to pick up those hints.

📌 Community Management

Nevertheless, there may be things you don't understand or have questions about.
This can naturally occur due to the nature of online courses.
That's why I've created a community where you can ask questions and get answers in real-time.
Feel free to join and ask anything. Also, I hope you'll share algorithm solutions with various developers and work through problems together.

📌 60% theory, 40% practice

This is a curriculum that starts with detailed theoretical explanations and ultimately progresses to solving actual problems from company assessments.

😨Concern Point 1😨.
I heard coding test languages are predetermined these days?

I heard that the coding test language is predetermined based on the stack you're applying for - like JavaScript for frontend and Java for backend?

That's correct. There are cases where the language is enforced.

I've taken coding tests at 38 places and only encountered this at 2 of them. trong số 38 nơi tôi đã làm bài kiểm tra coding.

Almost all the places you apply to will have virtually no language restrictions.

No matter what language you use to express it, interviewers also know that the ability to think through and solve problems is what's ultimately important.

😨Concern Point 2😨.
This isn't my main language?

You might be worried because it's not a language you've already learned.

However, I believe it's necessary to understand it as easily as possible with Python.

Algorithms are already difficult, and when complex syntax is mixed with difficult logic, the code becomes much harder to read.

When you first study, it's best to understand things as easily as possible, and then try expressing them in more complex ways later on.

It's also good to practice understanding through Python first, then expressing it in your own language.

If you understand the logic in Python, you can definitely express it in Java.

😨Ultimately, language is just a means of expression, and understanding the problem is what's most important.

And the easiest language to understand and solve problems with is Python.

[Updated July 20, 2025]

I've added supplemental code so you can solve problems in Java and Javascript as well, which many students have requested!
I haven't added explanations in those languages, but it would be great to view them as a way to review by looking at code with the same logic in different languages!

🎁 EVENT 🎁

There is a special benefit provided only to those who take the course.

There is a specially curated collection of algorithm problems based on actual questions I've encountered in 38 real coding tests.

You can think of this as a special problem set created for those who want to do additional problem practice beyond theoretical learning.
This problem set will be continuously updated, so you'll be able to prepare for algorithms in line with current trends!!

(This problem set is provided as a Notion link!)

DALL·E 2024-11-06 23.37.48 - Design of a special algorithm workbook cover titled 'Essential Algorithm Problems from 38 Real Coding Tests.' The cover is in a deep blue background w

I will give this problem set to those who write a course review!

Thank you.

Get it after verifying your course review in the algorithm community!

(The verification method is written in the very last lecture __)

That's not all

I'll even provide you with a developer job preparation guide (resume, portfolio, etc.)!

🎁 EVENT 2 🎁

After completing the course, if you pass, please share your course review + job transition success story in the open chat room!

As a token of our appreciation, we'll send you a coffee gift card

🎁 EVENT 3 🎁

If you submit the Google form through this link

🎟 We'll give you a discount coupon 🎟

🎁 EVENT 4 🎁

Pycharm IDE 3-month free trial provided!!

To support your development studies, we've prepared special benefits through collaboration with JetBrains.
You can use PyCharm for free for 3 months with the promotion code below!

✅ Promotion Code: HYUNJOONPARKxJB
✅ Benefits: 3-month free subscription for a single JetBrains IDE (e.g., IntelliJ, PyCharm, WebStorm, etc.)
✅ Valid Until: May 13, 2026
✅ How to Use😀😀

1. Access the official JetBrains coupon registration page

2.Enter the code and select your desired IDE

3. Check the license issued to your email

⚠ Important Notice:
This code is only available for new users who are using JetBrains for the first time.
(Only those who have never used a paid JetBrains license before can register)
(You can do this infinitely by creating new Google email accounts)

😆 Lastly, I'll emphasize just 2 things.

1. This course has gone through two thorough reviews, and all videos include subtitles.

You might think "Why does that matter?", but many courses are often uploaded without any review process., nhưng nhiều khóa học thường được tải lên mà không qua kiểm duyệt.

This course has undergone two rounds of review to carefully check subtitles and context, enhancing its completeness.

2. The textbook is 393 pages in total.

The materials are designed so that you can fully understand the content through them alone. I've systematically organized and presented the content to help you save time and learn as efficiently as possible.

2024.11.30 Update

Among the lecture feedback, there was a comment saying "I wish there were more example problems."

Based on this feedback, I've added bonus problems throughout the course materials.

You can think of problems with the 🎆 icon as bonus problems without separate explanation videos

2024.12.15 Update

Added textbook PDF download link

2025.1.13 Update

3-5. Added explanation for further improvement methods for Stack - thanks to zz gg

1-5. Added explanation of the criteria for the first non-repeating character in finding the mode - thanks to Oh Subin

3-9. Added explanation of the condition that among songs with the same play count, songs with lower unique numbers should be included first - thanks to sonjs7554

2025.5.18 Update

4-2 Animation error in video corrected - thanks to 애롱

2025.7.18 Update

Fixed selection sort output error in 3-3 textbook - thanks to 유개발

2025.7.20 Update

Java, Javascript problem solution code added

2025.10.15 Update

Practical Data Structures Library Comparison Table - thanks to 브루브루

2025.10.19 Update

Week 4 Homework Problem 1 boundary value logic correction and boundary value test addition - thanks to 한달안에 끝낸다

2025.12.7 Update

4-8 DP section BigInteger code and explanation added - thanks to xuv2

2025.12.13 Update

5-4 Input/output case correction - thanks to June

2025.12.24 Update

3-5 Input/Output case correction - thanks to giving0414

Recommended for
these people

Who is this course right for?

Someone who is just starting to prepare for coding tests
For those who feel overwhelmed by the vast amount of algorithm study material
For those who need problem-solving skills that can be applied immediately in real situations
Beginners who need explanation-focused teaching and step-by-step approach
For those who want to learn only the core algorithms that reflect the latest exam trends

Need to know before starting?

A very slight introduction to Python

Hello
This is

12,121

Learners

1,236

Reviews

239

Answers

4.9

Rating

Courses

🚀 토스, 포항공대 출신 | 백엔드 8년
🎥2만 유튜버 | 개발 콘텐츠 제작
📚 인프런 강사 | 누적 수강생 8,000+
👥 개발자 취업 커뮤니티 운영 중 (8,000+)
🧩 오픈소스 (Gradle, Spring AI 등) 다수 Contributor
📝38개 서류 합격 및 크몽 이력서 첨삭 100+회 이상 경험 (평점 5.0점)

코딩을 뒤집다, 딩코딩코. 쉽고, 연역적으로 이해되는 지식을 전달합니다.

인프런 인터뷰 링크!

Curriculum

All

56 lectures ∙ (15hr 33min)

Section 1. Algorithm Pre-test

2 lectures ∙ (17min)

Section 2. [Week 1] Time Complexity & Space Complexity

12 lectures ∙ (1hr 52min)

3. Class material link
4. 1-1. What to learn in Week 1
04:27
5. 1-2. Essential Program Installation
01:28
6. 1-3. Coding with PyCharm
02:54
7. 1-4. Getting Familiar with Algorithms (1)
07:52
8. 1-5. Getting familiar with algorithms (2)
26:00
9. 1-6. Determining Time Complexity
08:10
10. 1-7. Determining Space Complexity
08:17
11. 1-8. Asymptotic Notation
05:50
12. 1-9. More Algorithm Practice (1)
06:00
13. 1-10. More Algorithm Practice (2)
08:05
14. 1- 11. Week 1 End & Homework Explanation
33:16

Section 3. [Week 2] Array and Linked List, Binary Search Recursive Function

10 lectures ∙ (2hr 22min)

15. 2-1. What to Learn in Week 2
03:03
16. 2-2. Array and Linked List
11:43
17. 2-3. Class
10:06
18. 2-4. Linked List Implementation - 1
16:48
19. 2-5. Linked List Implementation - 2
20:10
20. 2-6. Linked List Problem
07:59
21. 2-7. Binary Search
18:40
22. 2-8. Recursive Function - 1
09:03
23. 2-9. Recursive Function - 2
12:03
24. 2-10. End of Week 2 & Homework Explanation
32:37

Section 4. [Week 3] Sorting, Stack and Queue, Hash

9 lectures ∙ (3hr 40min)

Section 5. [Week 4] Trees and Heaps, BFS and DFS and DP

9 lectures ∙ (3hr 2min)

Section 6. [Week 5] Kakao Samsung Line Actual Past Questions Breakdown

14 lectures ∙ (4hr 18min)

Published:

Last updated:

Reviews

All

367 reviews

5.0

367 reviews

yjym33
Reviews 29
∙
Average Rating 4.7
5
13% enrolled
The instructor explained everything in detail, making it easy to understand even for those who are new to the subject. The visual aids at the end were also easy to follow, so it was very helpful. - What I would like to see: It would be great if there were explanations and problem-solving for complex algorithms that might come up on the CoTe, such as the Bellman-Ford, BFS, and Floyd-Warshall algorithms.
sethgots7214
Reviews 1
∙
Average Rating 5.0
5
18% enrolled
It's been quite a while since I systematically studied algorithms. In practice, I often use libraries or frameworks, so I have fewer and fewer opportunities to directly contemplate and implement algorithms. This lecture allowed me to reorganize from the basics. In particular, I was impressed that it not only explained the concepts but also covered the way of thinking and approaches to solving problems in detail. Thanks to this, I was able to not only recall the concepts I had forgotten, but also regain the habit of thinking about how to write more efficient code. I think algorithms are not just for coding tests, but also greatly help to improve problem-solving skills. After building my basics through this lecture, I feel more confident in approaching new problems in the future. I highly recommend it to those who want to review from the basics!
lux
Reviews 24
∙
Average Rating 5.0
5
7% enrolled
I bought this course because of the thumbnail, but the content was even better. I majored in it and have experience as a developer, but algorithm problems were always difficult. I am gradually gaining confidence while taking this course😊 I set a goal of completing the course in 5 weeks, so I hope I can finish it well!! - Structure: Each topic is well organized step by step, so it naturally connects from basic data structures to actual past exam questions. In particular, I liked the fact that various approaches were introduced in the process of solving each problem. - Teaching ability: The explanations of the Dingcoding instructor are amazing, so it is easy to understand even complex algorithms. Even using visualization data👍🏻👍🏻 - Practical application: It doesn't stop at simply explaining the theory, but also covers solving actual problems and analyzing efficiency, so I think it will be very helpful for actual coding tests! Recommended for: I highly recommend this course to those who are preparing for coding tests or want to systematically build up their algorithm skills. If you have some understanding of Python grammar, I think you will gain a lot from this course. Rating: ⭐⭐⭐⭐⭐ (5/5)
- dingcodingco
  Instructor
  ㅋㅋnim!! Thank you so much for the detailed course review!! 😭😭😭😭 I really hope it was helpful!! Keep up the good work!!
bhn19979793
Reviews 2
∙
Average Rating 5.0
5
14% enrolled
I got a job without majoring in it, but I wasn't very prepared for algorithms, so I'm taking this course to supplement it. It's really easy to understand with the abundant materials and explanations~!! I was worried because I didn't use Python in my work, but fortunately, it's an easy-to-understand language ㅎㅎ
- dingcodingco
  Instructor
  bhn1997, I'm so glad you understood it well!! You'll definitely feel the advantages of Python as you code!! I really hope you can break the code through this lecture ㅎㅎ
gisu11028193
Reviews 1
∙
Average Rating 5.0
Edited
5
45% enrolled
I kept putting it off every day, but I've pulled myself together and started again. If you're encountering this for the first time, I think this will be the best course. When it comes to solidifying the basics, I doubt there's a better course at this price. What I hope for: It would be great if there were courses on more advanced algorithms after the basics.

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The Secret to Passing 38 Companies, Essential Algorithms for 2025 Coding Tests

Reviews from Early Learners

What you will gain after the course

🎯 Coding Test Master Class perfected through 38 real-world passes

2024 Latest Coding Test - Essential Algorithms 5-Week Completion Project🔥🔥🔥

Real reviews from students who passed after taking the course

✅ Here's what you'll learn.

The features of this course

I recommend this for those who

🥳🥳🥳 Real Student Reviews 🥳🥳🥳

😨Concern Point 1😨. I heard coding test languages are predetermined these days?

😨Concern Point 2😨. This isn't my main language?

🎁 EVENT 🎁

I will give this problem set to those who write a course review!

Thank you.

🎁 EVENT 2 🎁

🎁 EVENT 3 🎁

🎁 EVENT 4 🎁

😆 Lastly, I'll emphasize just 2 things.

1. This course has gone through two thorough reviews, and all videos include subtitles.

2. The textbook is 393 pages in total.

2024.11.30 Update

2024.12.15 Update

2025.1.13 Update

2025.5.18 Update

2025.7.18 Update

2025.7.20 Update

2025.10.15 Update

2025.10.19 Update

2025.12.7 Update

2025.12.13 Update

2025.12.24 Update

Creator of this course

Things to note before enrolling

Practice Environment

Learning Materials

Prerequisites and Important Notes

Recommended for these people

HelloThis is .css-1q3zd4q{text-decoration-line:underline;text-underline-position:under;text-underline-offset:1px;}

Curriculum

Reviews

dingcodingco's other courses

Similar courses

😨Concern Point 1😨.
I heard coding test languages are predetermined these days?

😨Concern Point 2😨.
This isn't my main language?

Recommended for
these people

Hello
This is