#133: Logic Masters '24 Qualification Round

I co-authored the qualification round for this year’s Logic Masters (the German puzzle championship), together with Thomas Fink (whom you might know as Phistomefel). This post contains all of my puzzles from the round, plus three bonus puzzles.

In a first for the blog, there are walkthrough videos for every (non-bonus) puzzle. Don’t expect too many of these in the future, but I might occasionally record them for contest puzzles.

Please also check out the full set over on LMD, Thomas’s puzzles are great, too. That page also has the instruction booklet, which contains example puzzles, in case you’re confused about any of the rules.

The puzzles below are presented in the same order as in the contest, i.e. in order of increasing solve time (on paper, at least). At the end of the list you’ll find three bonus puzzles: the Belarusian Snake was never meant to be part of the contest. I originally constructed it as a practice puzzle to post on LMD before the contest, but it seems we both forgot to actually do that (oops). As for the Turn-and-Runs, I constructed three different puzzles around the same gimmick (no crossings) of varying difficulties so we could pick one that best fit the difficulty distribution of the other puzzles after testing. We ended up going with the easiest of the three, so these two bonus puzzles are a little harder. All three puzzles use very different logic though and I’m quite fond of all three of them.

Chocolate Banana

Rules: Shade some cells so that all areas of orthogonally connected shaded cells are rectangular and all areas of orthogonally connected unshaded cells are not rectangular. A clue represents the size of its group of shaded/unshaded cells.

Belarusian Snake

Rules: Shade some cells to form a non-intersecting path which does not touch itself, not even diagonally. Each region must contain exactly three shaded cells. Regions containing an end of the path are shaded.

Tents (Hexagonal)

Rules: For each tree in the grid, place a tent in an empty adjacent cell, connecting to it. Tents may not touch one another. A clue given outside the grid represents the number of tents in the corresponding line.

Slitherlink (Crossing)

Rules: Connect some pairs of orthogonally adjacent dots to form a single loop. Two perpendicular line segments may intersect each other, but not turn at their intersection or otherwise overlap. Clues represent the number of edges drawn surrounding the clue (up to four).

Statue Park

Rules: Place each shape from the bank given outside the grid into the grid so that no two shapes share an edge and all unused cells form one orthogonally connected area. Rotating and reflecting shapes is allowed. Cells with black circles must be used by a shape, and cells with white circles must not be used by a shape.

Turn-and-Run

Rules: Draw an oriented loop through the centres of all cells. The loop can only intersect itself at the indicated crossings. The loop turns at each number clue. The value of the clue indicates the exact length of the segment leaving the clue before it turns again.

U-Bahn

Rules: Draw a continuous subway map into the diagram that runs horizontally and vertically from cell centre to cell centre and does not leave the diagram anywhere. The lines can branch or turn at the cell centres, but there are no dead ends. The numbers at the edge indicate how many of the corresponding segments occur in the corresponding row or column. The segments may also be rotated.

Inbox/Outbox

Rules: Divide the grid into regions of orthogonally connected cells. Each region must contain exactly one white and one black clue. Black clues indicate the total area of the largest rectangle fully contained within the region. White clues indicate the total area of the smallest rectangle containing the entire region.

Compass

Rules: Divide the grid into regions of orthogonally connected cells, each containing exactly one compass. A number in a compass indicates how many cells belong to its region that are further in the indicated direction than the compass itself.

Signpost Nanro (Aqre)

Rules: Place a number into some cells so that all cells with numbers form one orthogonally connected area and no 2x2 region is entirely numbered. Each region must contain at least one numbered cell, and every number in the region must be equal to how many numbered cells the region contains. A clue in a region represents how many numbered cells are in the region. Two cells containing the same number may not share a region border.

There may not exist a run of more than three consecutive numbered or unnumbered cells horizontally or vertically anywhere in the grid.

Castle Wall

Rules: Draw a non-intersecting loop through the centres of some cells. The loop may not enter outlined cells or cells containing clues. White cells with outlines must lie inside the loop, while black cells with outlines must lie outside the loop. Grey cells may either be inside or outside the loop. A number represents the sum of the lengths of loop segments in the indicated direction.

Meandering Words

Rules: Place a letter into some cells. The letters in a region must form an orthogonally connected chain of letters spelling out one of the words given outside the grid. Each given word must be used. Two instances of the same letter may not appear in adjacent cells, not even diagonally, and not even across region boundaries.

Bonus 1: Belarusian Snake

Rules: Shade some cells to form a non-intersecting path which does not touch itself, not even diagonally. Each region must contain exactly three shaded cells. Regions containing an end of the path are shaded.

Bonus 2 & 3: Turn-and-Run

Rules: Draw an oriented loop through the centres of all cells. The loop can only intersect itself at the indicated crossings. The loop turns at each number clue. The value of the clue indicates the exact length of the segment leaving the clue before it turns again.