Logic Masters Deutschland e.V.

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Play on F-Puzzles

Rules:

The grid above represents a city with a sudoku train running though it. The train line has 7 stops, numbered 1 through 7. Cells with a stop are shaded blue, and the stop's number is the same as the cell's digit .

The number of a stop is also the number of cells which are part of the track that touch the stop (either orthoganally or diagonally). The stops themselves are not considered part of the track.

The train starts on the track cell that touches stop 1, and goes along the grid visiting each stop in order (so the train track does not go to a cell that touches stop 7 before going to at least one cell touching stop 6. However, after at least 1 track cell has touched stop 6, a track cell can touch stop 7, so it could be the track visits 1 cell touching stop 6, then 7 cells touching stop 7, then the remaining 5 cells touching stop 6 for instance). The train goes through the entire city, such that all 2x2 regions in the grid have at least 1 track cell. The train's path along the track doesn't touch itself, not even diagonally . The train track may continue past the 7th cell that touches the 7th stop, but there is an end to the track (i.e the track has a start and an end, and does not form a single, continuous loop)

The railway required demolishing several skyscrapers to make way for the track. Clues outside the grid are regular skyscraper clues, except the height of any cells along the track is 0. Track cells can be part of a skyscraper clue's count, though only the first seen track cell will ever be counted (e.g. a row of 9 track cells would have a skyscraper clue of 1). Since as above, train stops are not part of the track, train stop cells have a normal skyscraper height.

For safety, a few level crossings (thermometers) have been installed as well. These act as normal thermometers (digits increase starting from the bulb). However, contrary to my first puzzle with a sudoku train, the level crossings are actual crossings, so exactly one cell on the crossing is on the track, and exactly one cell on the crossing is not on the track

(also, while not on theme- Normal sudoku rules apply)

Example:

See the below 6x6 grid for a valid example for a sudoku train with 4 stops. The 6x6 has a logical solution which you can try to familiarize yourself with the rules. You can try the 6x6 puzzle here.