Rules - Slitherlink

Slitherlink was invented by the Japanese puzzle company Nikoli.

1. Draw a single loop that connects the dots on the grid.
2. The loop may only travel horizontally and vertically, not diagonally (so all turns are right angles).
3. The loop may only turn at the dots.
4. The loop may not cross itself or branch off.
5. All numbers inside the grid indicate how many sides around it are in the loop.