The ultimate guide to recursion interviews in JavaScript. Developed by FAANG engineers. Practice with real-world interview questions and get interview-ready in just a few hours.

If you’ve ever struggled with solving problems using recursion, or if you have to brush up your skills for an interview, this course is for you.

We'll start with the basics of what recursion is and why it’s important before diving into practicing solving actual questions. You’ll have access to detailed explanations and visualizations for each problem to help you along the way. 

By the time you have completed this course, you’ll be able to use all the concepts to solve complex real-world problems. We hope that through practicing recursion, you will be able to ace all recursion related questions in interviews at top tech companies.

Recursion for Coding Interviews in JavaScript

# Problem Statement
Implement a function that takes a number `testVariable` and returns that row of the *Pascal's triangle*.

## What is Pascal's Triangle?

Pascal's triangle is a [triangular array](https://en.wikipedia.org/wiki/Triangular_array) of the [binomial coefficients](https://en.wikipedia.org/wiki/Binomial_coefficient).

The entry in the 
$nth$ row and $kth$ column of Pascal's triangle is denoted as: 
$${\displaystyle {\tbinom {n}{k}}}$$

For example, the unique nonzero entry in the topmost row is 
$${\displaystyle {\tbinom {0}{0}}=1}$$

With this notation, any element can be written as:
$${\displaystyle {n \choose k}={n-1 \choose k-1}+{n-1 \choose k}} 

<a href="https://commons.wikimedia.org/wiki/File:PascalTriangleAnimated2.gif#/media/File:PascalTriangleAnimated2.gif"><img src="https://upload.wikimedia.org/wikipedia/commons/0/0d/PascalTriangleAnimated2.gif" alt="PascalTriangleAnimated2.gif"></a> By <a href="https://en.wikipedia.org/wiki/User:Hersfold" class="extiw" title="w:User:Hersfold">Hersfold</a> on <a href="https://en.wikipedia.org/wiki/Pascal's_triangle">Wikipedia</a></a>

<a href="https://commons.wikimedia.org/wiki/File:PascalTriangleAnimated2.gif#/media/File:PascalTriangleAnimated2.gif"><img src="https://upload.wikimedia.org/wikipedia/commons/0/0d/PascalTriangleAnimated2.gif" alt="PascalTriangleAnimated2.gif"></a> By <a href="https://en.wikipedia.org/wiki/User:Hersfold" title="w:User:Hersfold">Hersfold</a> on <a href="https://en.wikipedia.org/wiki/Pascal's_triangle">Wikipedia</a></a>

Given a number, return a list containing the values of the Pascal's Triangle of that size.

Recursion Fundamentals

Iteration Vs Recursion

Recursion with Numbers

Recursion with Strings

Recursion with Arrays

Recursion with Data Structures

Conclusion

Challenge 2: Pascal's Triangle

Problem Statement

What is Pascal’s Triangle?