Card game simulation

Question

0.00/5 (No votes)

See more:

I wrote a card game simulation for a very simple card game. The simulation runs the game multiple times and doesn't display output except for the number of wins, losses, and win %. I ran multiple simulations of millions, 10s of millions, and even 100 million games, which took several minutes. After more than 1 million games the win % tends to cluster around 1.62%. However, the mathematical win % should be 1.8316% which was confirmed by a professor of mathematics. So I should be winning 1 of every 500 games more than I am. I've checked my code over and over including what I believe to be a good use of the random number generator and the proper way to shuffle a deck of cards.

I'm wondering if someone would be willing to write their own procedure to simulate this game and see what they get for results?

The game goes like this. Shuffle the deck. Then one by one place each card face up and call out, in order, "ace" "two" "three" ... "jack" "queen" "king". Then repeat until the end of the deck. You win only if each card does not match the called out value. For example, if you get to the 5th card and it is a "5" you lose. If you get to the 28th card and it is a 2 you lose. So, obviously, you test using the mod operator % 13. I don't want to bias another solution with a post of code, but thought someone might be interested to try it themselves and, if closer to the mathematical expectation, compare code.

Posted 30-Nov-12 3:40am

woj123

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Tim Corey · Accepted Answer · 2012-11-30T03:53:00

My thought on your issue is that you are probably running into an issue with the pseudo-random number generator. The problem is that it isn't truly random. For most instances, this isn't a problem but because you are generating such quantities, you might be running into a problem with it.

My suggestion would be to change your generator to increase its randomness and see if that brings you closer to your expected result. Here are some options for you to try:

http://stackoverflow.com/questions/1234094/how-can-i-generate-truly-not-pseudo-random-numbers-with-c[^]

As for us developing one as well, this isn't the place to ask for something like that. You won't get the exposure to your request that you want and it really doesn't fit as a question.