Hello again and happy Labor Day! Autumn is soon approaching (for some of the world, at least), so I hope you’re looking forward to the new season. What better way to start it than with a new puzzle?

The next entry is based on Galaxies (also known as Tentai Show). Sharon Braveheart has taken up a part-time job at Firewire Cafe, mainly to get leftover treats for free. Her job is to present platters of donuts in a way that will attract customers, so she has opted for a “symmetrical” approach. Your goal is to divide the grid-shaped platter into regions that meet the following conditions:

• Each region must have exactly 1 donut in it.
• You can only draw borders around the lines that make up the grid.
• The donut must be the center of the region’s rotational symmetry; in other words, if you rotate the region 180 degrees around the donut, it should have the same shape, position and orientation.

The pictures below depict a sample puzzle on a 5×5 grid, along with its solution. Some of the donuts, like the white one in the bottom left corner, do not sit cleanly within a grid square; this is intentional, and so it requires that the four squares around it are part of its region.

Now, can you solve the puzzle below and help Sharon arrange the platter?

The solution will be released in the next blog post. Also, if you tried the puzzle from the last blog entry, here is its solution below. I always find this type of puzzle fun to visualize in my mind, as if I’m looking at the skyscrapers from the top of a hill.