PlaySudoku.us
Evil · Puzzle #959
3
6
2
9
9
4
1
7
5
4
7
8
2
3
7
4
5
3
9
7
5
6
1
9
2
Techniques used
- Hidden Single
- Naked Single
- Naked Pair
- Naked Triple
- XY-Chain
- Forcing Chains
- Skyscraper
Sudoku has no math — you could replace the digits 1–9 with any 9 symbols and the puzzle works identically.
Sudoku has no math — you could replace the digits 1–9 with any 9 symbols and the puzzle works identically.
SAT solvers — used in chip design verification — can crack any Sudoku puzzle in milliseconds.
SAT solvers — used in chip design verification — can crack any Sudoku puzzle in milliseconds.