The stopping point is called the base case. You could almost write the factorial function simply as this:Īs you can see, as long as the initial value is above zero, this function will terminate. For example, factorial(5) is the same as 5 * factorial(4).

For example, factorial(5) is the same as 5*4*3*2*1, and factorial(3) is 3*2*1.Īn interesting property of a factorial is that the factorial of a number is equal to the starting number multiplied by the factorial of the number immediately below it.

The factorial of a number is computed as that number times all of the numbers below it up to and including 1. The classic example of recursive programming involves computing factorials. It’s also not an intuitive process when we give instructions to other people, we rarely direct them recursively.įor those of you who are new to computer programming, here’s a simple definition of recursion: Recursion occurs when a function calls itself directly or indirectly. Recursive thinking is difficult because it almost seems like circular reasoning. Examples are in Scheme and C.įor new computer science students, the concept of recursive programming is often difficult. This article introduces the concept of recursion and tackles recursive programming patterns, examining how they can be used to write provably correct programs. But as you’ll see, there are several techniques that can be used to minimize or eliminate these problems.

Recursion is a tool not often used by imperative language developers because it is thought to be slow and to waste space.

You dont know js recursion