Your Coding Teacher

Bash exercise: Read from file.txt and output all valid phone numbers to stdout. A valid phone number appears in one of the following two formats: (xxx) xxx-xxxx or xxx-xxx-xxxx No leading or trailing whitespaces grep '^(\d{3}-|\(\d{3}\) )\d{3}-\d{4}$' file.txt

I've been sick for a few days (still recovering). We'll have to postpone the call till next week

4 JavaScript interview questions Why does typeof null return object? What's the difference between Spread operator and Rest operator? What are closures? How to create an object without a prototype?

Some balanced binary search trees - Red-black: rules based on node colours - AVL: heights of left and right subtrees <= 1 - Splay: after every access, the tree is readjusted. - B-trees: balanced N-children trees. Used commonly in databases

"When in doubt, use brute force." - Ken Thompson

In Java, all classes inherit from othe Object class the following methods: - toString - equals - hashcode - clone - finalize - getClass - notify - notifyAll - wait They're available to any object you create, and you can override most of them.

Core reviews improve your codebase quality and they are an excellent learning tool.

vi 101 i - Insert Mode (edit the text) esc key- Command Mode. In this mode: :w - save work :w! force write :q - quit vi :q! -force quit 0 - beginning of line $ - end of line u - undo dw - delete till end of current word db - delete till beginning of current word

"XML combines the efficiency of text files with the readability of binary files" - Andrew S. Tanenbaum

And on the 7th day, God began debugging

Basic and extended regex are variations on the syntax of the pattern. With basic (BRE) syntax, characters like ? and + don't have special meaning unless prefixed with \ With extended (ERE) syntax it is reversed: the characters are special unless they are prefixed with \

Sometimes interviewers will intentionally give you a very vague, ambiguous question just to see how you react. Don't freak out. Expect this. The ability to tackle ambiguity is actually one of the points that you are being evaluated on.

Build things "just for fun" and put them in your CV. It's more impressive than you may think. Since not many people do it, it's an easy way to stand out.

There's only one value in JavaScript that is not equal to itself: NaN (Not A Number) $ console.log(NaN != NaN) true

Build projects around motivated individuals Give them the environment and support they need, and trust them to get the job done agilemanifesto .org

4 Interview tips - String problems can usually be solved as array problems - Sometimes it's easier to start processing the string/array *from the end*. - Ask if you can modify the input or need to create a copy - If it's a tree question, clarify if it's a binary search tree.

Load balancers in GCP vs AWS - Software-based (faster to start) VS run on EC2 instances. - Global VS Regional managed service - URL routing for HTTP vs HTTP & TCP - Can distribute traffic globally VS Only within a region

Statically-typed languages: the type of an entity (variable, object, ...) is known at compile-time. Ex: - Java - C - C++ - Scala Dynamically-typed languages: the type of an entity (variable, object, ...) is known at run-time. Ex: - JavaScript - Python - Ruby - PHP

Linux 101 A distribution is a collection of components that form a system. Hardware -> Kernel -> GNU Core -> X Server -> UI Examples: - Ubuntu - Debian - Fedora - CentOS - openSUSE

C++ related concepts - Class and structure are blueprint for objects. Structure elements are public by default while class elements are private. - An object is an instance of a class/structure - Unions can contain different elements, but only one at a time