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All right, so let's implement our recursive factorial function.

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So we will say cargo, new recursion.

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We'll go into recursion.

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And now we will open up our main address.

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So to keep it similar to how we talked about it in the previous lecture, we will make our own function

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called fact and we'll make our argument a i 32 num and we want to return an I 32 as well.

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All right.

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So we have a base case that we can look for in here and we want to make sure that num is greater than

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one, because if it's not greater than one, well then there's nothing else to do.

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So we can just flat out return one.

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Otherwise we want to return num times, fact of num minus one.

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And if you remember we do this because we have in factorial is equal to n times n minus one factorial.

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And we establish that this is equal to calling our factorial of n function and having it call itself

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again.

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So the recursion happens here of the result of n times factorial of n minus one, and that's exactly

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what we're doing.

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So we're passing in our parameter or our argument and we're saying we want to return that number times

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the factorial of num minus one.

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So to test this, we can come down here and we can print line

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and we just want to print out the factorial of five.

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And if we go run this, we will see that we have 120, which is correct.

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That is five times four times three times two, five times four, 20 times three, 60 times two 120.

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And that's all there is to it, to recursion.

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Right.

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So it's a it's a pretty simple concept and we want to make sure that.

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For it to be recursion that we just have to call ourselves.

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So we're going to look at a couple more examples of recursion.

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That way you get really comfortable doing it so that as we use it later on in this course, you are

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fully confident in your ability to understand what is what is going on.