Tag: Javascript

As a front end Web developer who likes to code, I think it's reasonable to start my own blog to document what I learned on web development, and there are multiple options to choose from when building a blog site, they are all viable options, I'll start from the one require no coding skills, all the way up to the one that needs the most coding skill :

As a react developer who builds a web app that can handle more than 50 WebSocket events that will be merged into state per second while keeping it 60 FPS, I spend a lot of times on tuning the performance on my web apps, and recently, when I was doing code review on a junior developer, I noticed some mistakes that will harm the performance of the web apps

Arrays and Strings

• if the order is not important, then the hash table might be a good candidate to reduce the time complexity.
• be familiar with all the methods for arrays and strings.

Linked Lists

• How to implement a Linked List structure?
• How to delete a node from a single Linked List?
• How to reverse a Linked List?
• The runner and dummy head

Bit Manipulation

• Negative Numbers: 3 => 011, -3 => flip 011 => 100 => 101 => prepend the first bit => 1101
• << && >>> Logical Shift => move every bit to the left/right, the firt/last bit will be cut off, then append/prepend the bits with 0

• Arithmetic Right Shift => shift values to the right but fill in the new bits with the value of the sign bit

• get ith bit =>

Recusrion and Dynamic Programming(DP)

Ways to approach:

• Bottom-up: Starting from the simplest case, then build a solution that on top of the previous one.
• Top-Down: The reverse of Bottom-up, less intuitive, but sometimes useful.
• Half-Half: They are usually seen on the bitwise operation and binary tree operation.

DP & memoization:

• Using recursion alone sometimes is...

System Design and Scalability

this section is more related to the back-end than the front-end, but it's good to know from a broader view:

• Communication: it's more important in the system design than dealing with a specific coding algorithm question. because most of the time, a lot of details won't be covered in the problem description, so the candidate should ...

Sorting and Searching

Thanks for https://www.bigocheatsheet.com/ for building this compact cheat sheet...

When starting my career as a software engineer, I felt overwhelmed by the algorithms, I didn't even know what is Big O. Knowing it will take lots of time to learn it, I try to avoid it.

After spending a year to get myself familiar with Javascript, I know that it's the foundation of computer science, not specific to any programming language, which means once I learned the concept, I don't have to

It's useful when looking for a subset with certain quality in a stream, like Kth largest Element or Kth smallest Element.

The keypoint is understand how to get the parent index when bubble up, and left child index and right child index when trickle down, below is the implementation with comments:

I have been using Typescript for some time, but still feels something absent on learning it, then I notice that beyond the basic syntax, I'm not familiar with the design pattern of Typescript. Sure, It's not actually a language, but since it's so widely used in my work, I feel that I should invest more time in learning the advanced usage of it.

I'll start from the definition...

Cycle Sort can be used to handle special case input, which is consecutive integers, it's a decrease and conquers approach:

The name came from how it approaches the inputs: starting from the leftmost spot and figuring out which number goes there, then recursive call on the remaining elements, which looks like a cycle.

The complete list of the description and prevention of each security vulnerability can be found here.

Now let's look at each one more closely:

A01:Broken Access Control

Common ones include the following:

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
CWE-201: Insertion of Sensitive Information Into Sent Data

I've done on setting up a boilerplate project with 4 statistic analysis tools for React framework(using create-react-app), you can find it out here.

The tools included in the project are:

1. Eslint (mainly used to check code errors)
2. Prettier (a code formatter with little configuration rules )
3. Stylelint (checking on style...