A line of lookout towers, four to a row. Fill the 4×4 ridge with towers of heights 1–4 so every row and column holds each height exactly once. The numbers around the edge are lookout reports: how many towers are visible from that side, where a taller tower hides everything behind it. Three ridges per run. Score: 100 per ridge, −10 for each failed check, −15 per hint. Higher is better.
Setting up the first ridge...