X-Wing Example Walkthrough
The best way to understand X-Wing is through concrete examples. Let us walk through how X-Wing appears in real puzzles.
Example 1: Number 5 X-Wing
Situation: Number 5 can only go in columns 3 and 7 in row 2. Similarly, in row 8, 5 can only go in columns 3 and 7.
Result: In columns 3 and 7, 5 can be eliminated from all rows except row 2 and row 8.
Row 2: [x,x,5?,x,x,x,5?,x,x] / Row 8: [x,x,5?,x,x,x,5?,x,x] → Rectangle complete
Common X-Wing Patterns
Row-based X-Wing (most common): Same column positions across 2 rows
Column-based X-Wing: Same row positions across 2 columns
Watch out for "almost" X-Wings: If a row has 3+ possible positions, it is not an X-Wing