Intergalactic Journey
(Published on 18. December 2020, 23:02 by SebastianSimon)
After many years of development, humanity finally reached their goal to build a spacecraft to scour nearby galaxies for habitable planets. In order to visit as many galaxies as possible, the spacecraft needed to avoid the centers of the galaxies; instead it must glide exactly between them, through the emptiness of space, so as to avoid getting attracted by the gravitational pull of the galaxies. But even previously unknown galaxies needed to be watched out for. At the end of its journey, the spacecraft shall return to the earth and enrich scientific advancement with the gathered photographic material.
This is a combination of two standard puzzles: Galaxies and Slitherlink. The goal is to solve both of them in the same grid, satisfying the rules described below.
Galaxies: A galaxy is a region which is rotationally symmetric around their center point, consisting of orthogonally connected cells, including their center point. The edges making up the perimeter of these rotationally symmetric regions must be marked to delimit different galaxies from each other and from the border of the grid. An edge may not be drawn in the inner region of a galaxy. Every single cell is part of exactly one galaxy and two distinct center points do not overlap eachother. 1×1 galaxies are allowed.
Slitherlink: Draw a single, closed loop through the edges of the grid. The digits in the cells determine how many edges of the cell are part of the loop.
Only cells within the 10×10 grid below may be used, as well as all edges around these cells.
In total, there are 19 galaxies in the grid. Some, but not all, center points of these galaxies are given with white circles. Center points can be placed either in the middle of a cell, on the edge between two cells, or on the intersection between four cells. Once the missing center points are determined, the same Galaxies rules apply for these galaxies, as described above.
The Slitherlink loop only passes through the perimeters of the galaxies, i.e. the loop never enters the inner region of a galaxy.
The loop touches the perimeter of each galaxy at least once.
Solution code: The sizes of galaxies (in cells) which are on the inside of the loop, in ascending order. (Example: Galaxies of size 1, 3, 3, 4, 6, 10, and 14 cells on the inside of the loop → 133461014.)
Comments
on 16. January 2024, 21:16 by The Book Wyrm
Very good puzzle!
This is a very interesting ruleset, and makes for some nice interactions between the galaxies and the slitherlink.
The unknown galaxies made it quite tough, but not unreasonably so.
on 19. December 2020, 12:55 by SebastianSimon
@cdwg2000 Example of expected solution code added.
Thank you very much for your feedback!
on 19. December 2020, 12:51 by SebastianSimon
@cdwg2000 Do you mean I should include an example of the expected solution code?
on 19. December 2020, 12:44 by cdwg2000
Very beautiful puzzle, the difficulty is worth 4 stars or higher.
on 19. December 2020, 10:32 by SebastianSimon
@Eggr Thanks for the feedback! I was not sure at all how difficult this really is; it’s really hard to judge, for instance, how easy it is to simply guess the right shape of the galaxies, or eyeball the shapes based on the Slitherlink clues. I’ve updated the difficulty.
on 19. December 2020, 07:47 by Eggr
Unless I was missing something obvious, this is harder than 3 stars. The 3 extra center points made it really hard for me to make logical deductions about the potential galaxy shapes.
