Zip is the most physical of our puzzles. You draw a single line through the grid, joining the numbers in order and filling every cell. It's satisfying to get right, and very easy to get wrong.
The rules
- Draw one continuous path that starts on 1.
- Pass through the numbers in order: 1, 2, 3 and so on, ending on the highest number.
- Visit every cell exactly once, moving up, down, left or right.
- Thick bars are walls. The path can't cross them.
Five tips for your first solves
1. Corners are traps
A corner cell has only two neighbours. Unless the path starts or ends there, it must come in through one neighbour and leave through the other. So you often know exactly how the path runs through a corner before you get there.
2. Don't leave a cell behind
If your path passes a cell that now has only one way in, that cell has become a dead end. The path can only finish there, and it must finish on the last number. Before each move, look at the cells beside you.
3. Don't cut the grid in two
If the path seals off a pocket of empty cells, you can never come back to fill it. Hug the edges and fill regions completely before moving on.
4. Read the numbers as a route plan
The distance between two numbers matters. If 4 and 5 are right next to each other but many cells remain, the path probably makes a long detour between them.
5. Work from both ends
Your finger has to start on 1, but your eyes don't. Look at how the path must arrive at the final number, and at the corners near it.