In a 9x9 grid, there are already numbers filled up. The goal is to fill up the rest of the boxes with numbers as humanly fast as possible. Rules are that:
- You fill in a number from 1-9
- All numbers need to be unique vertically or diagonally, for example all 9 numbers on the first row must be unique and no repeats.
- Numbers in a small 3x3 cube must be unique
A fun brain teaser. I've seen bookstores selling various kinds of books with Sudoku puzzles. Looks simple, but it takes time and the more you do the faster you will become. There are strategies and methods to resolving each of them.
It is very fun if you ask me. I've been trying to beat my own record by doing the puzzles faster and faster... You never get the same puzzle because it can have millions of combinations.
My latest Sudoku record is about 5 minutes for easy & about 11 minutes for medium.