Microsoft Solitaire 10000000 Shuffles

I have run across many Solitaire games that indicate that they match the same first 1000000 Shuffles from the Microsoft Solitaire which allows the player to play the identical game scenario in both programs. I can only think of two ways this can be done, and neither seem plausiable

  • The Game ID is used as the seed for a random number generator, and both apps somehow produce the same random sequence from the same seed, I find this unlikely as it would require AN IDENTICAL “random” generator, while I guess is possible, I find it unlikely
  • All these apps have a database with the card sequences… This however would require a minimum of 52meg just to store this data

I always thought that two machines running the same OS on the same processor would produce identical “random” numbers given the same seed. No?

That is probably true… But these apps I mentioned are across ALL platforms (Windows, macOS, and iOS, and maybe even Linux) yet all purport to duplicate the same first 1million deals from Microsoft Windows Solitiare

something about random
wiki/Pseudorandom_number_generator

Perhaps the algorithm has been reverse-engineered? But if it’s based on the Random, I propose a test among the interested members here. This is my code and results on my Catalina-driven Mac:

dim r as new Random

r.Seed = 1.0
AddToResult r.Number.ToString( "#,##0.0######" )
// 0.8526603

r.Seed = 10000.0
AddToResult r.Number.ToString( "#,##0.0######" )
// 0.2153194

r.Seed = 100000.0
AddToResult r.Number.ToString( "#,##0.0######" )
// 0.8891194

Mojave produces that same result, as does WIn10… but that just means the Xojo has a consistent algorithm

I think the tables are stored … elsewhere, and Xojo just accesses them the same as any other software.

I think…