Recursive factorial function

Hi,

Trying my hand at recursive functions and found a simple recursive function for factorials and found this online :

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I don't understand how this works. When num eventually reaches 1 won't the function return 1 instead of the complete factorial ?

Thanks,
amphi

A recursive function repeatedly calls itself, so there needs to be some way of stopping this. Suppose the function is called with a value of 3 - then the first bit is ignored and the line:

myfact = num * myfact(num - 1)

is executed. However, this calls the function again with a reduced number, so that particular execution is suspended while it tries to evaluate

myfact(2)

This again will reach the line:

myfact = num * myfact(num - 1)

and needs to get a result from

myfact(1)

This indeed returns 1, so the previous line can be executed (i.e. 2*1) and then the fist call can also be executed (i.e. 3*2*1).

Hope this helps.

Pete

Thanks a lot Pete. Somehow couldn't wrap my head around the recursive function & base case. I assumed that each time the function called itself it "lost" the previous call result as I thought a variable was needed when it doesn't.