Detour — Nikoli Turn-Count Loop Puzzle

Draw a loop through every cell. Numbers show turns per region.

Goal: Draw a single closed loop visiting every cell exactly once.

Rules:
- Click between two cells to draw/erase a line segment
- Each numbered region shows how many turns the loop makes inside it
- Unnumbered regions have no turn limit
- The loop must not branch or cross itself

Controls:
- 1 = Draw mode, 2 = Erase mode
- H = Hint, R = Clear, Enter = Check
- Esc = Menu