Draw a single closed loop passing through some empty cells in the grid. The loop connects centers of adjacent cells, makes only right-angle turns or goes straight, and does not intersect or cross itself.
The grid contains some outlined white and black cells that cannot be part of the loop. Outlined white cells must be inside the loop; black cells must be outside the loop. Numbers and arrows refer to the total sum of the lengths of straight loop segments along the given direction. (An equivalent way to understand these values is by putting a dot each place the loop crosses a cell border. Each numbered arrow then points to that number of dots.)
Notes:Variants:
- With grey cells: Draw a single closed loop (without intersections or crossings) passing through some empty cells in the grid. The grid contains some bordered or colored cells that cannot be part of the loop. Black cells must be outside the loop; white cells (with heavy borders) must be inside the loop. For grey cells this information is unknown. Numbers and arrows refer to the total sum of the lengths of loop segments in the given direction.