adding solver code and other bits of changes, need to record more often

Created by  GPeTJGuaAryfKVDHpJLoiRAiv9jDq5aAapfNcWjYu16v  on August 14, 2023
KP5ZHGFKZZV35ZEH2AZW2HAFF6XXTK4XVLUI3D62ZTBPNOTQJONAC
Change contents