GetHashcode - Int too small capacity?

Right now I'm implementing a Vector3 struct only with INTs. i did some research to figure out how to write a proper hashcode for 3 Ints, and i stumbled upon this page (also referenced by many other pages talking about hashcodes):
http://stackoverflow.com/questions/...m-for-an-overridden-system-object-gethashcode

Code (CSharp):

1.  
2. public override int GetHashCode()
3. {
4.    unchecked // Overflow is fine, just wrap
5.    {
6.        int hash = 17;
7.        // Suitable nullity checks etc, of course :)
8.        hash = hash * 23 + field1.GetHashCode();
9.        hash = hash * 23 + field2.GetHashCode();
10.        hash = hash * 23 + field3.GetHashCode();
11.        return hash;
12.    }
13. }
14.  

Now, i implemented the HashCode as follows:

Code (CSharp):

1.         public override int GetHashCode()
2.         {
3.             int hash = 17;
4.  
5.             hash = hash * 486187739 + x.GetHashCode();
6.             hash = hash * 486187739 + y.GetHashCode();
7.             hash = hash * 486187739 + z.GetHashCode();
8.             return hash;
9.         }

My question is - the number returned is incredibly large, and can actually not be stored in the returned INT. How come, this is the suggested prime number then? Am i missing an important step in the implementation?

Cheers and thanks upfront!

 

I think it will just truncate/overflow silently, if the number cannot fit.
Provided overflow checking is disabled or if enabled, the code is written inside a 'checked' statement.

 

Yes. You removed "unchecked". The "unchecked" keyword is what makes it ignore the overflow and return anyway. If you get rid of that, it's going to throw an OverflowException.

 

@methos5k @makeshiftwings
Thanks a lot! That makes much more sense now! .

 

Awesome.