The gap between the real world of practice and the real world of lectures is much bigger than you think. It is true that the programs written in actual practice are much more complex, much more difficult, and much larger in scale. It is not easy to narrow that gap. Beginners who are watching the lecture feel that even a little complexity is difficult, and if it is too easy, most of them cannot do anything even after completing the entire lecture. So after much thought, I mixed the difficulty level between easy and difficult, and focused on creating content and examples that are not covered elsewhere. I think there may have been parts that felt difficult and complicated during that process. Or maybe it is because I lack the ability to explain. However, I wish you had used the Q&A board to ask questions about which parts are difficult and which parts are not solvable. Anyway, thank you for your good opinion, and I will try to improve my ability to explain more easily. Thank you.