Hamiltonian Killer Thermo
(Published on 4. October 2025, 08:00 by Kaktuslav)
Rules: Place the digits 1–9 exactly once in each row and each column of the grid.
Draw a directed path that moves orthogonally between cell centers and visits every cell of the grid exactly once.
Each of the 27 cages can be entered by the path at most once (i.e. the path must visit all cells of a cage in a single continuous run before leaving it).
The path acts as a thermometer with respect to cage totals: as the path moves away from its starting cell, the sums of the cages it visits must strictly increase.
Digits may not repeat within a cage.
Solution code: Row 9
Comments
today, 17:44 by Bourinas
The path is very easy to get once you get the case X constraint. Very nice puzzle
on 6. October 2025, 23:53 by AdarshN
Very unique, very lovely, very satisfying!
on 6. October 2025, 13:21 by mscha
Beautiful puzzle! Highly original.
on 4. October 2025, 19:36 by Crona
Once I had an idea of the path I was speeding through the first half. I'm not sure if I missed something obvious but the bottom half took me quite some time to figure out.
on 4. October 2025, 17:52 by Qodec
Very smooth! (Like butter, not soap.)
on 4. October 2025, 17:01 by Manta-Ray
Very nice, thanks!
on 4. October 2025, 16:50 by Exigus
Lovely puzzle. Reminded me of Jugglers "the wall" even if it is very different. Thanks!
on 4. October 2025, 13:17 by OutOfMyMindBRB
Very enjoyable - thanks :-)
on 4. October 2025, 10:26 by Adrian71
Nice, original puzzle! I found it very enjoyable, thanks for sharing
