Puzzle 128: Pentomino pipes

Here’s something new, a puzzle I made when a friend asked for “something with pipes”. I think the general idea of finding a pentomino net works quite well, though I’m not convinced of the details of the mechanics in this version. In particular, some other kind of clues might work better, e.g., giving the connection dots.

pentopipes

Rules Place a full set of pentominoes onto the grid lines. (Each pentomino cell maps to a vertex, and adjacent vertices are connected by an edge, like the clues from Puzzle 82.) Each edge may be part of at most one pentomino. If two pentominoes touch at a vertex, there must be exactly two pentomino edges touching that vertex. There must not be any vertices with a single edge.

Wherever a vertex is marked by a letter, that vertex must be one of the five vertices of the pentomino corresponding to that letter. There may be still be a second pentomino using that vertex.

Example with pentominos F, U, V, Y.

pentopipes-example

Puzzle 126: Yin-Yang Fences

And quickly another post to hide that terrible Domino Construction. In contrast, this one has a nice solving path, but will you find it?

yinyang-fences-2

Rules Solve as a standard Slither Link. In addition, all cells outside the loop must be connected, and there must be no 2×2-square of cells that is entirely inside or outside the loop.

Or see the instruction booklet.

Puzzle 125: Skyscrapers Domino Construction

Another Skyscrapers Domino Construction, to bang your head against. If that’s your thing.

Edit I’ve since convinced myself there’s a reasonable way through. Still really hard, but no longer a puzzle I feel bad about.

skyscraper-domino-construction-2

Rules Place the given set of dominoes in the marked domino tiles. Whenever two dominoes touch by an edge, the adjacent numbers must be the same. Clues outside the grid are skyscraper clues: They indicate the number of visible skyscrapers when looking along the corresponding row or column from that point, where each number represents a skyscraper of that height. Skyscrapers are blocked from view by those of greater or equal height.

Or see the instruction booklet.

Puzzle 124: Skyscrapers Domino Construction

Is it just me, or are there more uncommon types on this round than previously? Anyway, below there’s a Skyscrapers Domino Construction. Again these were on the 24 hours this year. This one is probably not typical, but I think it came out quite well.

skyscraper-domino-castle

Rules Place the given set of dominoes in the marked domino tiles. Whenever two dominoes touch by an edge, the adjacent numbers must be the same. Clues outside the grid are skyscraper clues: They indicate the number of visible skyscrapers when looking along the corresponding row or column from that point, where each number represents a skyscraper of that height. Skyscrapers are blocked from view by those of greater or equal height.

Or see the instruction booklet.

Puzzle 123: Countries

Countries is another type from the Russian GP that I first saw in Budapest this year. This one should show that some of the deductions that seem almost correct aren’t always.

You might want to resolve it with full clues to get something more like the GP puzzles, though I suspect that that bypasses quite a bit of the logic.

Edit Fixed an ambiguity (second try), thanks Neil!

countries-1
Rules Subdivide the grid into orthogonally connected areas (“countries”), each containing exactly one letter. Numbers outside the grid give the number of cells in that row or column that are part of the first country in that row or column.

Or see the instruction booklet.