Mirrored from Sudopedia, the Free Sudoku Reference Guide
An X-Wing is a fish pattern involving 2 rows and 2 columns.
It is a single-digit solving technique that allows the player to eliminate candidates.
Try to find an X-Wing; page down to see the Solution.
It is in rows 1 and 4.
Make sure that both rows contain only 2 candidates each and that these candidates are confined to two columns. In this example, the columns are 2 and 5.
Now we can eliminate the remaining candidates from these two columns.
A total of 9 candidates can be eliminated from these two columns.
When 2 Rows contain only 2 candidates each, and candidates are located in the Same two columns, you may eliminate all other candidates from these 2 columns.
Example. fish diagram:
There are 2 candidates in row 2 and in row 8, marked X. Both candidates are located in the same columns 2 and 8. All other candidates in these 2 columns, marked with a red asterisk, can be eliminated.
This page was last modified 06:13, 9 January 2009.