The ultimate guide to recursion interviews with strategies developed by FAANG engineers. Practice with real-world interview questions, detailed explanations, and visualizations to prep faster.

If you’ve got an interview coming up and want to brush up on your knowledge, or if you’ve ever struggled with solving coding problems using recursion, you'll find this course helpful.
 
You’ll start with the basics of what recursion is and why it’s important before diving into what it looks like in practice. You’ll see how recursion can help you solve a variety of different math, string, and data structure problems by using interactive code playgrounds that you can execute directly in your browser. You’ll have access to detailed explanations and visualizations for each problem to help you along the way.  
 
By the time you’re done, you’ll be able to use what you’ve learned to solve complex real-world problems and even advance more easily through your interviews at top tech companies.

Recursion for Coding Interviews in Java

```Java
if(startIndex >= len)
        return;
````

```Java
if(startIndex <= len)
 return;
````

```Java
if(startIndex >= len/2)
        return;
````

The task is to print the array using recursion.
```Java
public static void printArray(int array[], int startIndex, int len)
{
    System.out.print(arr[startIndex] + " ");
 
    // Recursively calling printArray to print next element in the array
    printArray(array, startIndex + 1, len);
}
```

What should the base case of the following code be?

The task is to print the array using recursion.
<pre><code class="language-Java">public static void printArray(int array[], int startIndex, int len)
{
 System.out.print(arr[startIndex] + &quot; &quot;);
 
 // Recursively calling printArray to print next element in the array
 printArray(array, startIndex + 1, len);
}
</code></pre>
What should the base case of the following code be?

return (arraySum(array, n - 1) + array[n - 1])

return (arraySum(array, n - 1) + array[n])

The task is to return the sum of array of elements
```Java
public static int arraySum( int[] array, int n)
{	
 //base case
	if(n <= 0)
		return 0;
	else
		//recursive case
}
```
What should the recursive case of the above-mentioned code be?

The task is to return the sum of array of elements
<pre><code class="language-Java">public static int arraySum( int[] array, int n)
{	
 //base case
	if(n &lt;= 0)
		return 0;
	else
		//recursive case
}
</code></pre>
What should the recursive case of the above-mentioned code be?

Solve this Quiz!

Solve this Quiz!

This lesson will check your knowledge on recursion with arrays.

Fundamentals of Recursion

Iteration to Recursion

Recursion with Numbers

Recursion with Strings

Recursion with Arrays

Recursion with Data Structures

Quick Quiz on Recursion with Arrays!