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Easy · Puzzle #636
2
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9
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7
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8
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9
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8
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9
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9
8
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6
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9
2
When a box has only two empty cells, you know exactly which two digits fill them.
When a box has only two empty cells, you know exactly which two digits fill them.
X-Wing: if a digit appears in exactly two cells in two rows, and those cells share the same two columns, eliminate that digit from those columns elsewhere.
X-Wing: if a digit appears in exactly two cells in two rows, and those cells share the same two columns, eliminate that digit from those columns elsewhere.