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Compass (223)

Instruction:
Shade some cells so that all remaining white cells form a single connected area. Shaded cells can't touch each other by a side. There can't be any 2x2 area of white cells. Cells with arrows or stars can't be shaded. Arrows indicate that this is the only direction to travel to the star horizontally and vertically over the white cells without backtracking.

Reference: WPC 2017 (11)