Solving 600 10x10 jigsaw puzzles in a row would easily exhaust you without posing any challenge at all.
In this case it’s more like 600 sudoku that introduce and teach new methods without needing an external guide, and that is great for me
alt Hacker News
In this case it’s more like 600 sudoku that introduce and teach new methods without needing an external guide, and that is great for me