Home
Screensavers
Sudoku
Daily Sudokus

Sudoku Solver

Techniques
Double Block Line
Double Block Line is similar to Block Line except... doubled! With this technique,
two
blocks and
two
lines are taken into account.
Consider the sudoku below.
4
4
4
4
4
4
8
6
5
2
3
4
4
4
4
4
In
the left and right blocks
, the value 4 can only exist in
the cells marked with a small 4
.
If a 4 exists in
the top row of the left block
, then there must be a 4 in
the bottom row of the right block
. Alternatively, if
the bottom row of the left block
contains a 4, then there must be a 4 in
the top row of the right block
.
Wherever the two 4s are, we know that
the top and bottom rows of the center block
cannot contain a 4. So we can remove 4 as a possible value for those cells.
Copyright©2020 Decabit Software
Last Updated: 9/24/2020 12:00:23 PM CST