#### Someone had wikipedia open when they wrote that

EDIT: Added book recommendation at the bottom; should be readable for any half-decent *cough* "programmer".

So a little bit snarky but secret sharing systems usually have some huge caveat. That's why we don't already use what would be a brilliant thing (I don't want to argue what constitutes shared secrets (not secret sharing) so let's take the "I give you a string of abstract bytes, you give me some pieces back I can give to a fixed number of people such that [the schemey bastard threshold > 50% OR SOMETHING)"

It's really not that easy. Doing it on paper is even worse - computers can at least do the tedious crap we can't do well.

So to answer your question: "none" - unless you are also like these numptys and willing to risk so much on some C++ thing you wrote once - from how you suggest it I kinda doubt you've got past rule 1:

1) Don't write your own crypto.

With age and a fuck-tonne of maths spanning abstract algebra, measure theory, combinatorial optimisation and a few others (of which I've spent 6 years veering towards in no rush) AFTER the obvious stuff (like not counting undergrad) and the thought of breaking this rule WITH $190m on the line should allow one to cut a cigar with your anus (should it rest on your implementation).

Then you relax as you realise "wait the GPL says "no warranty fuckers!" ;)"

Lastly: the problem is actually not too difficult for small divisions, for example 3 people you have "1/3rd" as the only fraction in play when it comes to colluding. A big problem that quickly bites is you get an n! (for sharing among n) trying to work out what order to put the pieces in.

Conversely (for me anyway, I've come to accept that the statement "no one else gives a shit") - and this is what I find interesting - if we give up on the "suppose we want exactly n parts given out and all n required to unlock the secret, with no probable way to work out the order (this has a formal meaning)" above (which for reasons stated is impractical for n after a few, and for n small enough the bastard ratio is huge (eg 67% if 2 people collude with n=3)) it actually leads to some quite interesting ideas

None of which are practical of course ;)

Book: Foundations of Cryptography - Volume 1: Basic Tools - Oded Goldreich

A lot of this is English so you can just open it somewhere and "enjoy" - which is why I mention it. I know PDFs of it can be found. PLEASE DON'T THINK THAT THIS IS ANYTHING TO DO WITH WRITING CRYPTO STUFF THAT YOU SHOULD TRUST it's pure theory and is one of the few books I've found that spans both sides of the formal/informal divide.