Let’s say someone asked you to write a method that can find the factorial of a number. I’ll show you how. And then I’ll show you how to do it recursively. Remember recursion?
But first, see the definition of Factorial from wikipedia, for those of you who didn’t do math in school.
5! = 1 x 2 x 3 x 4 x 5 = 120
So here is the method. It takes a number and returns its factorial. This is a standard way of doing it, or you can refactor the code and make it more concise
Public Function Factorials(Byval n As Integer) As Integer if n<1 Then return 1 Dim res As integer = 1 For i As Integer = 1 to n res*= i Next i Return res End Function
Using Recurcion to find the factorial.
So imagine that you have to use recurcion to get the same results. Not difficult at all. You just change the code a little bit and have the method call itself. See the code below.
Public Function Factorials(Byval n As Integer) As Integer If n<1 Then Return 1 Else Return (n * Factorials(n-1)) End If End Function
So that is it. Both methods work fine and return the same results. Another little bit on recursion.
Till next time, yours truly.