# Puzzle 99: Hochhausblöcke

Hochhausblöcke is a neat skyscraper variant that showed up in the Rätselportal round. They’ve usually been less regular, but from the instructions it was clear that the one on the competition would be an 8×8-grid. I thought there was a good chance of a puzzle without outside clues, and certainly the interactions involved there need more practice, so I tried to construct such a puzzle. I kept running into dead ends, started doubting that they exist at all, and threw the computer at the problem. It turns out that there’s a lot, but they’re rare enough: there’s a good 200000 excluding symmetries, or a little under 1% of all clueless grids you could write down. It should not be unreasonable to find one by hand. Here’s one.

Rules Place numbers from 1 to 4 in each cell so that each row and column of each 4×4-block contains all numbers 1 to 4. Circled numbers are valid skyscraper clues for the adjacent grid (for both adjacent grids in the central corners). Uncircled numbers are not valid skyscraper clues for the adjacent grid (for neither adjacent grid in the central corners).

# Puzzle 98: JaTaHoKu, cryptic

Last JaTaHoKu for now, a JaTaHoKu with cryptic clues. I made a triagonal one, too, but didn’t get around to rendering that yet. Maybe later.

Rules Place numbers from 1 to 6 into some empty cells, such that each row, column and region contains each number exactly once. Clues within the grid are Tapa clues; the numbered cells form a valid Tapa solution with respect to these. Clues along the bottom and right edges are skyscraper clues. Clues along the top and left are Japanese Sums clues, with question marks standing in for unspecified digits. (I.e., 10 would be two question marks.)

Some digits have been replaced by letters. Equal letters correspond to equal digits, different letters to different digits.

# Logic Masters results and puzzles available

Just to note that the LM puzzles and results, subject of my recent rant, are now available. And I should note that the Summon is indeed not that bad. Enjoy, it’s a really fun set!

# Puzzle 97: JaTaHoKu, cylindrical

Another JaTaHoKu, this time cylindrical.

Rules Place numbers from 1 to 5 into some empty cells, such that each row, column and region contains each number exactly once. Clues within the grid are Tapa clues; the numbered cells form a valid Tapa solution with respect to these. Clues along the bottom and right edges are skyscraper clues. Clues along the top and left are Japanese Sums clues, with question marks standing in for unspecified digits. (I.e., 10 would be two question marks.)

The grid wraps around from top to bottom. Clues along the top act as Japanese Sums clues in order, starting at any group of numbers. Clues along the bottom act as Skyscraper clues, starting at 1. (So for example, a clue ‘1’ is impossible.)

# Puzzle 96: Ecken- und Kantenrundweg

As a bit of a breather before posting more JaTaHoKus, here’s a puzzle for one of the new types, at least I hadn’t seen it before. It was on the mixed round of the Logic Masters. It’s an “edge and corner fences”.

Rules Draw a single loop consisting of vertical and horizontal segments between dots that does not touch or cross itself. Clue numbers indicate the number of adjacent edges and corners that are used by the loop.

# Puzzle 95: JaTaHoKu

Another JaTaHoKu, this one using the full rule set. It’s probably a bit easier than the first one. Note that the given 4s in the grid are Tapa clues.

Rules Place numbers from 1 to 5 into some empty cells, such that each row, column and region contains each number exactly once. Clues within the grid are Tapa clues; the numbered cells form a valid Tapa solution with respect to these. Clues along the bottom and right edges are skyscraper clues. Clues along the top and left are Japanese Sums clues, with question marks standing in for unspecified digits. (I.e., 10 would be two question marks.)

# Puzzle 94: JaTaHoKu

Another JaTaHoKu I just made, to prove to myself that it’s possible to make accessible JaTaHoKus. You might want to solve this one before the previous one.

Rules Place numbers from 1 to 5 into some empty cells, such that each row, column and region contains each number exactly once. Clues within the grid are Tapa clues; the numbered cells form a valid Tapa solution with respect to these. Clues along the bottom and right edges are skyscraper clues. Clues along the top and left are Japanese Sums clues, with question marks standing in for unspecified digits. (I.e., 10 would be two question marks.)

# Puzzle 93: JaTaHoKu

Here’s a first (Ja)TaHoKu, which I made to prepare for the Logic Masters. Mostly an exercise in the interaction between the Tapa rules and the equal number of cells per row/column/region; that part seems to have potential as a Tapa variation. Would you have thought that even without rooms, the one Tapa clue implies that the mirrored cell has to be shaded?

Rules Place numbers from 1 to 4 into some cells, such that each row, column and region contains each number exactly once. Clues within the grid are Tapa clues; the numbered cells form a valid Tapa solution with respect to these. Clues along the bottom and right edges are skyscraper clues.

# Championship report: Logic Masters 2016

I participated in the German Logic Masters on Saturday. Ulrich Voigt won the play-offs, ahead of Martin Merker, Philipp Weiß and Nils Miehe; I placed fifth. Puzzles and results should be published at the page linked above at some point. I’ll probably be posting some puzzles I made in preparation in the future; for now some thoughts on the tournament.

# Puzzle 92: Transparent Kuromasu

Here’s a Transparent Kuromasu. Like the Horse Snake last week, this type occurred on Prasanna’s transparency-themed round at the Polish championships in back in April.

Rules Shade some cells, so that shaded cells don’t touch by edge, and such that all unshaded cells are connected by edge. Clues (which may be shaded) indicate the number of unshaded cells that can be seen in horizontal and vertical direction, including the clue cell.