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X-Wing

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.

Example

Try to find an X-Wing; page down to see the Solution.

image:X-wing-x1.png

It is in rows 1 and 4.

image:X-wing-x2.png

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.

image:X-wing-x3.png

A total of 9 candidates can be eliminated from these two columns.

How it works

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:

image:X-wing.png

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.