PRS-500 KAKURO for PRS-500/5

[Clemenseken]

Hi!

I've been developing a KAKURO game even before I posted my "Christmas gift MahJonG" last year.
(Actually my "Cacuro" was ready and playable then; there were so many problems that I started MahJong Instead.)

Now I changed and simplified its layout. But there still are some bugs to eliminate...

So - my question is: is there anybody here who knows a set of rules (I do not mean source code) how to avoid "double/exchangeable solutions" for a given sum?
(Or is a manual control necessary in any way?)

Attached is a screenshot with two example cases.
The upper one shows two identical sums - so their groups of numbers could be exchanged.
The lower one shows two different sums that nevertheless allows a simultaneous switching of each of their numbers.

I might try to invent a very complicated cross-checking algorithm ... but then I might fail with it!

I hope there is a mathematician here who's willing to dump my nose into a very simple, ingenious and obvious solution to get at a failsafe one !!!

If I get help soon, my "Cacuro" will certainly be ready in a short time.

Thanks to all, Clemens