little math/programming problems April 2023

[ThomasF]

(05-02-2023 08:03 PM)David Hayden Wrote:  Here's my C++ code. Does anyone spot a problem? Maybe this is a case of rand() showing it's limitations?

Hi David!

I assume this is due to the limitations of rand().
With different seeds I get the following result (ie your code but added seed initialization).

Code:

  srand (time(NULL));

Code:

Average of 5.48456 rolls starting with 5 dice
Average of 5.48837 rolls starting with 5 dice
Average of 5.48826 rolls starting with 5 dice

Using another random generator (PCG), I get the following result:

Code:

Average of 5.49419 rolls starting with 5 dice
Average of 5.49255 rolls starting with 5 dice
Average of 5.49275 rolls starting with 5 dice

Edit: All runs used 5 dice and 10M simulations.

Cheers,
Thomas