Post
Topic
Board Gambling
Re: FairDice.biz: new bitcoin dice game; only 0,8% house edge; FREE BITCOINS!
by
avencard
on 11/08/2013, 18:11:03 UTC
Dice64,
Look at the long text above "Roll" etc buttons. For me this is:
79ede5fd0267edccc5f2faa965ec689625cae8ab209bc764b608e9a2613fbc94
This is SHA256 hash of server seed, which will be used for next roll.
The roll result for me was 5.
Make a roll. Click "i" button to view details about roll you just did:
Server seed: 151d74125854c103abadc770f4eb5e99                        
Client seed: 8617075205573747000

hash("sha256", "151d74125854c103abadc770f4eb5e99") === 79ede5fd0267edccc5f2faa965ec689625cae8ab209bc764b608e9a2613fbc94

So for now everything is OK.

Now we use the validation script:

$server_seed = "151d74125854c103abadc770f4eb5e99";
$client_seed = "8617075205573747000";

function str2int($str) {
   $int = 0;
   foreach (str_split($str) as $char)
      $int += $char;
   return $int;
}

mt_srand(str2int($server_seed . $client_seed));
$roll = mt_rand(1, 6);
echo "Roll result is " . $roll;

Just run this on your web server or PHP CLI. It should print:
Roll result is 5

It confirms that my site is provably fair.

Quote
Also can you provide your calculations on how you came to the assumption that you have a 0.8% house edge?

(6-(2+1.4+1.2+1.1+0.25))*(100/6)  Wink