It's about 1200 lines, the original solution was only 170 and i'm pretty sure i could cut that down. Originally i had a line in that plugged the code back into itself with some of the cells fixed, it would then do this until there weren't any 0s left. It worked fine in sudoku solver #4 but for some reason in this it was breaking out early and giving me lots of the values still undecided. After a day of trying (and failing) to fix it I just copied and pasted the bits that worked :p