Every square shows an arrow, except the last one, which shows a star. Number the squares 1, 2, 3 … all the way to the star, so that each next square lies somewhere along the line its arrow points — next door or right across the grid.
Some squares already show their number. Link squares together into chains; as soon as a chain contains a given number, every square in it knows its number.
Start from the corners and edges: an arrow pointing at the edge only has a few squares to choose from.
Number every square from 1 to the star so that each next square lies somewhere in the direction of the arrow on the square before it.
The full guide, with a worked example and common mistakes: How to play Signpost Path.
Yes — any distance along the arrow’s line, as long as it is exactly in that direction.
An unnumbered chain: the square marked a+2 comes two after the square marked a.
Yes — every puzzle here is checked to have exactly one solution.
Open the Signpost Path Solver, enter the arrows and numbers, and press Solve.