1-2 pattern

Level: Intermediate

A 1-2 arrangement along a border confirms the mine cell.

This pattern appears when a 1 and a 2 are neighbors along the border of an open area. The 2 requires both of its adjacent cells to be mines, while the 1 requires only one of them to be, so the two conditions lock together.

Working out this relationship often confirms the cell at the far end of the 2 as a mine. Conversely, the cell the 1 shares becomes safe and can be opened.

The 1-2 pattern is the building block of longer wall patterns like 1-2-1 and 1-2-2-1. Get comfortable with the short 1-2 first.

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