Static void Fact(int n) in C#'s methods lesson

Question

I think that there may be an error in the definition of Fact. 0! Is defined to be 1.
The code in the question used "if(num == 1){....}", if you ask for 0! infinite recursion occurs. If the test was "if(num <= 1){...},
The problem is solved, see code fragment below.

namespace SoloLearn
{
class Program
{
static int Fact(int num) {
if (num <= 1) {
return 1;
}
return num * Fact(num - 1);
}
......}

Answer 1

Yes you're right regarding the fact that 0! = 1.

It really depends on the assumption of the integer provided as if we really want to be pedantic, negative numbers shouldn't be allowed as well. 😉