Sudoku solving technique · Pro
Y-Wing
Three cells with two candidates each: a hinge and two wings.
What is a Y-Wing?
A Y-Wing uses three cells each with exactly two candidates. One "hinge" cell can see two "wing" cells. The hinge shares one candidate with each wing, and the wings share a different candidate with each other. That shared wing candidate can be eliminated from any cell that sees both wings.
How to spot a Y-Wing
Look for cells with exactly two candidates. A hinge, say with 1 and 2, sees two wings: one with 1 and 3, one with 2 and 3. Whichever digit the hinge takes, one of the wings becomes 3. So 3 can be removed from every cell that sees both wings.
- Difficulty
- In Sudoku Pro, this technique belongs to the Pro level.
- Learning path
- Technique 14 of 20 on the learning path
An example from the app
| Pattern (purple). Candidates 1, 2 | Cell related to the pattern. Empty | Cell related to the pattern. Given 4 | Pattern (purple). Candidates 1, 3 |
| Cell related to the pattern. Empty | Given 3 | Empty | Given 2 |
| Cell related to the pattern. Empty | Given 1 | Given 2 | Given 4 |
| Pattern (purple). Candidates 2, 3 | Given 4 | Empty | Affected cell (orange). Candidates 1. Eliminated 3 |
Small digits are candidates. Crossed-out digits can be removed in this step.
- Pattern (purple)
- Affected cell (orange)
- Cell related to the pattern