Broken Sign Blog
#043: Rail Pool (Partial)
4 October 2022This is a variant I’ve been meaning to try out for ages (though I technically did with the triangular Rail Pool). There’s no particular reason why I made Rail Pool a “full” loop genre, though I suppose most region-based loop genres are full or impose rules on the unvisited cells. But in principle Rail Pool works just as well without that constraint.
Rules: Draw a non-intersecting loop through the centres of all cells. Some boldly outlined regions contain number clues. If a straight loop segment visits any cells of a clued region, its length must match one of these numbers. Each number must correspond to at least one such loop segment. Question marks represent any positive integer, but numbers cannot repeat within a region.
Variant: Partial — The loop does not have to visit every cell.