@ArrZarr
While you're right about the fact its learning from scratch its worth pointing out that there are many problem solving (well search algorithms really) that can solve sodoku with merely a list of rules. Even a simple program can use CSP (constraint satisfaction problem) to solve sudoku from the simple restrictions of 1-9 on a row and 1-9 in a 3*3 block - I had one on a pi zero that would solve it the moment you put in the last number required to solve it and if I could be arsed it could be modified to run on https://sourceforge.net/projects/gnusim8085/ if you upped the memory to 32k.