The XY-Wing technique is an advanced Sudoku solving strategy that helps you eliminate candidates in certain complex scenarios. It involves three cells that form a specific pattern, allowing you to deduce the value of one or more cells.
How to Identify an XY-Wing
An XY-Wing pattern consists of three cells with the following characteristics:
Cell X: This cell has two candidate numbers: X and Y.
Cell Y: This cell has two candidate numbers: Y and Z.
Cell Z: This cell has two candidate numbers: X and Z.
Cell X and Cell Y must see each other.
Cell Y and Cell Z must see each other.
Cell X and Cell Z must NOT see each other.
How the XY-Wing Technique Works
If the above conditions are met, you can eliminate the candidate number Z from any cell that is seen by both Cell X and Cell Z.
Example of the XY-Wing Technique
Tips for Spotting XY-Wings
Look for cells with only two candidates.
Focus on cells that see each other, but not all three.
