Blogs

After the huge attention gained by deepseek R1, I have seen a good amount of people immediately went to looking for censorships (which are expected to exist), laughed at it, and looked down on it. They totally missed the points and these behaviors made them look like slaves of their very own defense mechanism1. Deepseek did make some techonological breakthroughs. Indeed the censorship is a defect of such a great product. However making jokes on it with its censorships is just like catching grammatical errors in an insightful article and disdain the article because of that. Yes, grammatical errors are errors, catching itself could be useful, but doing that for attacking an insightsul article is another thing. It just misses the point. ...

Just added support for tikzjax since I received some feedback about my hand-drawn diagrams are hard to read…now I can use nice graphs like these: source: https://tikzjax.com/ source: https://tikzjax.com/ source: https://tikz.net/ ...

Disclaimer: The author’s knowledge about the legal system by no means applies to anywhere outside of his homeland. But what is legal or illegal should be similar enough for the discussion below - at least for first world countries, I guess. That said, the author is not a lawyer and does not have accurate knowledge of any concrete laws. But one does not need to know (too many of) them for this article. ...

Why ignore 50% of what we know about the data1 Everyone learnt binary search in Algo 101. It is the fastest way (among comparison based searches) to find an element in a sorted array. All you need to carry out the algorithms is the comparison between the target element and the element at the current position. It is widely applicable because it assumes so little from the data. But for many real life problems, we do often know something apart from merely the comparison between the two numbers. For examples: ...

Ladder of abstraction Well the title is obviously a tweak of the “ladder of abstraction”. For those who does not know, “ladder of abstraction” refers to the classic essay by Bret Victor. I am kind of stealing this terminilogy for the reader to visualize climbing up and down on the ladder of abstraction to make it easier to explain the nature of different jobs. The main question this blog post deals with is: ...

Relaxation as a result of mastery, instead of a prerequisites In many sports/ crafts that I have experienced, relaxation is considered by many the prerequisites of mastery: In playing piano, your fingers, wrists, arms and shoulders have to be relax or you will find it extremely hard to press the right keys fluently; In online games that require fast reactions, rookies hands are stiff and they press buttons with unnecessary strength and range of motion, which stops them from pressing right buttons at the right time smoothly; In jiujitsu, being reasonably relax helps you to perform efficient moves, saving your energy and gives you more choices in different situations in which you have to adapt and react quickly. Mainstream arguments I have seen in the above fields are that relaxation is a prerequisite of getting good at these skills: “You have to relax or your chords sound horrible!”, “you have to relax to improve your techniques”. Yet most people have to go through a good amount of practice untill they become relaxed and start being good at those skills. Did they not understand how to relax their bodies when they were beginners? Everyone knows how to relax their bodies - just lie on a comfortable massage bed and you will be relax. The hard part is being relax while doing things that we are not good at. ...

Counting binary trees I was thinking about of the problem of balancing a binary tree, and my mind stumbled across to the question “How many different binary trees with labelled nodes can you make without changing the traversal order?”. After figuring out the answer myself I realized that the numbers of such binary trees are just Catalan numebrs (I was not really into combinatorics - now I am). For example, the following has traversal order 1->2->3->4->5->6->7 ...

Defining the machine by describing it In Sipser’s Introduction to the theory of computation, a alternative way of defining a Turing machine (other than defining the formal 7-tuple, which is a PITA) - by its “description”. Example (from the proof of $A_{TM}$ is deciable): M = “On input <B, w>, where B is a DFA and w is a string: 1. Simulate B on input w. 2. If the simulation ends in an accept state, accept . If it ends in a nonaccepting state, reject .” ...

My pc is overheated how do i cool it down because it is my life1 Someone said that chatGPT will replace Google. Some kids/ early teenagers do often ask chatGPT for things that could have been found by Googling. I really hate the idea of replacing search engines by chatGPT. The problem I have with it is not really about AI, but about how do we interact with it. When we were kids and learnt how to use search engines, we acquired the skills of capturing important parts of the questions in our minds and turn them into keywords. Bashing questions like “my hard disk is full how can I get more space” usually get worse results than things like “hard disk space full solutions” as their counterparts. ...

Introduction Recently I am trying to reverse engineering a simple Windows desktop game made with Unity. I took a look on some reference but found that the setup can be a bit frustrating. This post is attempting to make the setup clearer and more followable. Reference links are listed below. Tools Our target is to decompile and debug the Assembly-CSharp.dll inside the folder <game root folder>\<GANE_NAME>_Data\Managed\, which contains custom code the game developer wrote, not the code of Unity or other frameworks. It is written in C#. We need the below tools: ...