Question

What does the following algorithm return?
f(n){
if (n < 2)
return 1
else
return f(n – 1) * n:

Answer 1

Would it not depend on the value of 'n'?

Answer 2

This looks like the recursive algorithm for finding the factorial of n.

Answer 3

Let's assume 'n' is 3,

It would return 3X2 = 6. How is that the factorial?

Answer 4

3*2*1=6

Answer 5

well it is in that case, i just realized but what if it was 4?

Answer 6

4*3*2*1=24

Answer 7

It just multiplies 4X3, not 2 and 1.

Answer 8

f(n-1) * n

Answer 9

it multiplies \(f(3)*4 =6*4=24\) since \(f(3)=6\)

Answer 10

looks like the recursive definition of factorial right?

Answer 11

so n!

Answer 12

exactly.

Answer 13

yes, that is it. multiply n - 1 th number by n

Answer 14

Ok thanks

Answer 15

Alright. I'll take your word for it.