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

Iteration means repeating some steps to achieve the desired outcome. 

Iteration means repeating some steps to achieve the desired outcome.

Iterative code is a block of code that runs in an `if`condition.

Iterative code is a block of code that runs in an <code>if</code>condition.

Recursive code has no overhead time.

Recursive code is slower than iterative code as it not only runs the program but also has to maintain stack memory.

Recursive code is slower than iterative code as it not only runs the program but also has to maintain stack memory.

Recursive code can be visualized using a stack.

Recursive code can be visualized using a stack.

The iterations in the iterative version turn into parameters in the recursive version.

The iterations in the iterative version turn into parameters in the recursive version.

In the following function, what is the **base case**?
```javascript
function foo(n) {
    if (n == 1) { 
        return 1;
    }
    else {
        return n + foo(n - 1);
    }
}
 ```

In the following function, what is the base case?
<pre><code class="language-javascript">function foo(n) {
 if (n == 1) { 
 return 1;
 }
 else {
 return n + foo(n - 1);
 }
}
</code></pre>

Recursive functions usually take more memory space than non-recursive functions. 

An iterative function can be replaced by a recursive function. 

Recursion enables you to give a natural, straightforward, simple solution to a program that would otherwise be difficult to solve.

Which of the following statements are true?

Which of the following statements are true?

In an iterative function, we express the function in terms of itself.

In an iterative function, we express the function in terms of itself.

This Quiz will take maximum 10 minutes.

This Quiz will take maximum 10 minutes.

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Now that you have learned the differences between iterative and recursive methods of solving problems, we will only be focusing on recursion for the rest of the course.

In the next chapter, we'll be solving problems related to numbers using recursion.

Recursion Fundamentals

Iteration Vs Recursion

Recursion with Numbers

Recursion with Strings

Recursion with Arrays

Recursion with Data Structures

Conclusion

Test Your Knowledge 2

Quiz on Iteration Vs.