2017-07-15

Leetcode: Combination Sum II

ProblemGiven a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combi

Coding

2017-07-09

Why is Kafka so fast

As we all know that Kafka is very fast, much faster than most of its competitors. So what’s the reason here? Avoid Random Disk AccessKafka writes everything onto the disk in order and consumers fetch

Coding

2017-05-18

kafka in a nutshell

IntroductionKafka is a distributed publish-subscribe messaging system that is designed to be fast, scalable and reliable. It can be used in data analysis, stream processing and other similar tasks. Th

Coding

2017-05-15

what does "this" refer to in javascript?

Introductionthis in javascript is always a mysterious thing. Some programmers who have written a lot of javascript code still cannot tell the value of this every now and then. So today, I decided to w

Journal

2017-05-15

re-embrace hexo and hueman

About a month ago, I started writing blogs in Chinese using WordPress. I stuck to the plan for about several days then decided to use English instead. The reason is unbelievably simple: typing English

Coding

2017-05-13

An Illustration of Various Encoding Schemes

What are encoding schemes?Encoding schemes are ways to store and retrieve characters in computers. For example, in ISO-8859-1(which is one of various encoding schemes), we use 01100001 to denote a, an

Coding

2017-05-10

Serialization and Deserialization in Java

IntroductionSerialization: a process which converts a Java instance into a bunch of bytes, so it can be stored in disk/database or transferred through network. Deserialization: the opposite of Seriali

Coding

2017-05-07

the machanism of garbage collectors in Java

There are several garbage collectors in Java, each has its specific usage scenario. To understand garbage collection, we first have to understand how heaps are divided in Java. Heaps are divided into

Coding

2017-04-23

Inheritance in Javascript

Javascript uses prototype chains to make inheritance work, that’s a little odd given that other OOP languages usually use class and extend. So to fully understand inheritance in javascript, we first h

Journal

2017-03-29

Where to go

I haven’t written my blog for a long time, partly it’s due to my sheer laziness, partly because I gathered nobody would even find it, let alone read it. But anyway, I decided to write something tonigh

Archive: 2017