sudoku

The problem with the tough Sudoku puzzles is they take longer and so I stay up later.  I always say to myself that I'll just do one more puzzle. Well then it's 30 min later than I thought it would be.  I didnt notice much difference betrween the moderate and the easy puzzles. But tough takes me at least 10 minutes longer. I'll have to test out diabolical sometime soon. I remember when i first started workign on these puzzles the first one took moe well over 2 hours. Now on the same site I have them done all the time in under 15. I need a stop watch to better time myself. It's also hard when I tlak on aim at the same time.