Example of O(n!)?

Question

What is an example (in code) of a O(n!) function? It should take appropriate number of operations to run in reference to n; that is, I\'m asking a

Answer 1

@clocksmith You are absolutely correct. This is not calculating n!. Nor is it of O(n!). I ran it collected the data in the table below. Please compare column 2 and three. (#nF is the # of calls to nFacRuntimeFunc)

n #nF n!

0    0      1
1    1      1
2    4      2
3    15     6
4    65     24
5    325    120
6    1956   720
7    13699  5040

So clearly if performs much worse than O(n!). Below is the a sample code for calculating n! recursively. you will note that its of O(n) order.

int Factorial(int n)
{
   if (n == 1)
      return 1;
   else
      return n * Factorial(n-1);
}