Recursion is a method of solving a problem by breaking it down into smaller problems that have the same solution. Recursion can be difficult to understand, but it's also really useful. In this blog post, we’ll cover the basics of JavaScript recursion and show you how to use recursion in your own code. We use recursion all the time without even realizing it. When you call a friend and they ask to call you back, that’s recursion. When you search something on Google and it gives you links to other websites with more information about that subject, that’s recursion. Even reading this sentence is an example of recursion! And if you like pandas or any other kind of cuddly animals, then you’re going to love this article about recursive pandas! Let’s get started...

What is Recursion?

Recursion is a method of solving a problem by breaking it down into smaller problems that have the same solution. Let's take a simple example of finding the largest number in a given list. If you were to write the code for this, you would use a for loop that iterates over the list of numbers and compares each one with each other number to find the largest. Now, let's say we had a really large list of numbers. With the for loop, we would have to do a lot of comparing, which could take a long time. Instead, we could use a method called recursion. With recursion, we first start by choosing a number from the list that is as close to the last one as possible. That would be the one right before the last one in the list. Then we check that number against the next number in line, which would be the number right after the one we chose. If the number we chose is larger than the number after it, then the number after that number is the biggest number in the list. If the number we chose is smaller than the number after it, then the number before it is the largest number in the list.

Defining Recursion

A recursive algorithm uses a function that calls itself. In other words, whenever you call a function (method), it calls itself again and again until it finds a result. Some algorithms are easier to implement recursively than others. Finding the largest number in a list, for example, is a perfect use case for recursion, because the function will call itself until it finds the largest number. Doing something like sorting numbers is more difficult to do recursively, because you have to keep track of what has been sorted and what has not been sorted. You'll also notice that recursive functions get more complicated as the problem becomes more complicated. It will feel like the function is doing more work than it should. This is because we are calling the function again and again, and each time we call the function, it calls itself again.

When to use recursion

As we mentioned above, recursive algorithms are great for when you have a problem that can be broken down into smaller sub-problems. Some examples where you might want to use a recursive algorithm are finding the largest number in a list, calculating factorials, and finding a number's digit pattern. You can use this handy table to help you decide when you want to use a recursive algorithm. Recursion has many applications in Computer Science and is often used to solve problems that have the following properties: - The problem can be broken into sub-problems of the same type - The sub-problems have a solution that depends on solutions to smaller sub-problems - The sub-problems can be solved easily enough to not break the code's execution time.

Conclusion

Recursion is a useful method of solving problems, especially when you have a problem that can be broken down into sub-problems of the same type. It can be difficult to understand and implement, but it will get the job done. If you need to find the largest number in a list, factorials, or a number's digit pattern, then recursion is the best method for the job.