Introduction Before start our tour of recognizing real numbers, I will introduce natural numbers first. This is a trivial thing for most of us, because we all use them in real life, and we know mo...

Here are something about git I didn’t know before, and I write them down for reviewing lately. Git Diff git diff To see what you’ve changed but not yet staged git diff --staged or gi...

Hyper Link If we add a link like this: [link](some url), it will take us to the destination on the same page. If you want to open it on a new tab, we can write it like this [link](another url...

If you are familiar with C++, you must be aware of its STL(standard template library) which consists of Containers, Algorithms, Iterators, Function Objects and Adapters, it’s powerful but also diff...

I got most knowledge about git from here. Files in Working Directory According to this. Remember that each file in your working directory can be in one of two states: tracked or untracked. Tr...

Before reading this article, you might want to read Implement A Tiny Regular Expression first for understanding more easily. Simplify the NFA It’s not easy to simplify an NFA directly, but to si...

A Simple Example First, let’s take a look at an easy regex example from LeetCode. Given an input string s and a pattern p, implement regular expression matching with support for ‘.’, ‘*’ and: ...

Introduction to Regular Expression What Is Regualar Expression As a developer, we may be more or less familiar with regular expression(also known as regex or regexp). It is a way to decribe a str...

As an algorithm, what kind of problems can dynamic programming solve? First, let’s check out a problem Climbing Stairs from LeetCode. You are climbing a staircase. It takes n steps to reach th...

There have been a lot of instructions about how to set up a blog on Github, but it still cost me 3 nights to finish. So I believe that recording what I had done when built this blog may help others...