Ronaldo Vitto Lewerissa

Software engineering learning documentation.

So You Wanna Learn JavaScript? (Part 2)

As of my last post on So You Wanna Learn JavaScript, I promised to put on several websites which I believe is rudimentary to enhance your JavaScript problem solving and algorithm skill.

So, besides on intensifying your knowledge on the concept, you need to actively put it on practice. Therefore these websites are really useful in making it happen.

Lets get straight down to it.

Free Code Camp

It's actually not design specifically for this purpose, yet Free Code Camp (FCC) is one of the best free open source website you could find to practice your JavaScript skill.

FCC mapped out to produce skilled web developer with tons of projects (which probably kind of what differentiate it from other sort of camps).

free code camp javascript algorithm practice

It has up to 150 algorithm scripting practice (on average) for JavaScript itself!

Pretty nice, right :)

You won't find common algorithm pattern come into practice (binary search, divide and conquer, etc). It will pivot on your ability to solve problems.

Here's one of it's advance algorithm scripting problem:

free code camp algorithm problem

It's nice to see how they even provide some helpful links you can check on:

helpful link free code camp

The test case you probably wondering, they spring it up so you'd know where you did wrong.

free code camp test case

One nice thing about them, is the awesome smooth user interface. free code camp UI


Plenty suggest CoderByte too. They have an organized sections of challenges difficulty, ranges from easy to hard.

I saw on the other day where Hack Reactor, the coding Bootcamp which specialized in JavaScript, ask their prospective students to practice on this site before going on their technical interview. There is a private section for you to prepare specifically to several bootcamp admission, including Hack Reactor, App Academy, and Fullstack Academy. They also provide a job interview questions for top companies like Google or Microsoft. Too bad they put on charge for you to access it :(

One thing I hate is their lousy UI. Kind of buggy, so you probably want to check out an online editor such as, and set the language to JavaScript.

One quick preview of it:

coderbyte user interface

There are currently 36 easy challenges, 33 medium challenges, and 45 hard challenges. See if you can solve them all :)

They have point system determined by the accuracy of your code and the time you need to solve it.

Code Wars

One of the best and recommended by many due to it's "war" feel and touch. I'm pretty sure many of you will love Code Wars.

Many of their problems (known as kata) is made by the users, so it keeps growing and growing. In terms of difficulty, you can find it ranges from 1-8. They call it kyu. So, there will be questions mark with 1 kyu until 8 kyu. You will start of with 8 kyu rank, and will level up gradually as you finish the challenges.

One sample question of a 7 kyu kata:

sample problem of code wars

You can define your own test cases:

code wars user interface

One awesome thing about this website is that you can see solutions by other "warriors" and vote for which you consider the best practice and clever. You'd find new ways of solving the problems, techniques you wouldn't realize before, which is GREAT!

best practice code wars

That's all from me, let me know what you think by leaving a comment!

I'll try to come up with more websites for you to try. Cheers :)

Written by Ronaldo Vitto Lewerissa

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