#cheatsheets

Although there is a wealth of information on the internet for things like data structures, recursion, and algorithmic complexity, sometimes it's easier to have it all right there at your fingertips. Or at least, I think it is.

Anyway, I've been preparing for a technical interview using Codecademy and I've found a wealth of cheatsheets for these topics and I'm going to share them all with you guys!

Disclaimer: I primarily code in Java so these are mainly going to be Java-centric. However, the theoretical aspects of these concepts are universal!

Of course, it's best to learn these concepts and use these as references once you understand them, but you can also use them as a sort of guide for your own learning.

All of these links lead to the cheatsheets on Dropbox.

Regular Expressions

Regular expressions can honestly be a bit of a learning curve, but they are EXTREMELY powerful when it comes to their matching capabilities. Don't underestimate how useful they can be!

Java Inheritance and Polymorphism

Once you learn how to properly use inheritance and polymorphism, you'll be doing significantly less work and you'll be able to create a sort of barrier between the code working behind the scenes and the users. Very nice.

Hash Maps

HASH MAPS. If you are storing and retrieving information, chances are you're going to be using a hash map. One of the most useful non-linear data structures. Important to clarify: dictionaries are hash maps. Java added dictionary functionality recently.

Sorting and Searching

Find your data, folks! Sort your data! Sort your data to use binary search! Please. I'm begging.

Nonlinear Data Structures

All good for storing data in a hierarchical way! Binary search trees show up super often in interview questions so make sure you have a good grasp on not only coding one, but using one effectively.

Linear Data Structures

Linear data structures should be your go-to if you're not dealing with a hierarchy. The basic structure at the bottom of literally every other linear data structure is linked lists and nodes, so make sure you are incredibly well-versed in them.

Graphs

Graphs! They're great for modeling networks, and they also make for great thought experiments when you think about how to traverse them. Social media tends to use them a lot.

Algorithmic Concepts

Ah, recursion and time/space complexity. Recursion is incredibly useful in teaching you how to make more efficient algorithms. On the other side of the coin, time/space complexity helps you analyze just how efficient an algorithm is. For technical interviews, you need to know how to use recursion and dynamic programming as well as how to calculate the complexity of the code you write.

(also, here is a reference to time/space complexities of a bunch of sorting algorithms and data structures. they also make posters!)

My next Yu-Shan cheatsheet, for the Bureau of Seasons. This is a pretty easy bureau to depict in infographic form! ;)