# Puzzle No. 484-487 : Polish Qualifier Puzzles [Ex-Contest]

Check this post for reference on this blog’s 3 main types of posts from now on. I’ll post smaller sets like this one here, and keep I’m hoping to start a patronage system of my own for bigger sets. More on that later.

Right, just about got this in today. I won’t be home over the weekend, so whether I get a sample of the Instructive tagged post out depends on getting an internet connection where I’ll be staying. I’ll be back on Monday though, so will have it up at latest by Monday night.

This set might seem to have some tough puzzles for a National qualifier (not finals), but I was told that there were many easy puzzles already. Two of the puzzles are types I saw in a book purchased from team Japan at the WPC. It is a collaborative work featuring Serkan Yurekli and many Japanese authors. I’ve changed one rule slightly for Heyawacky block (more an omission than a change) but I prefer it this way personally. Anyway, here they are. Enjoy!

Rules –

484 – Yajilin.

485 – Heyawacky Block – Blacken some cells so that all remaining cells must be connected orthogonally. Any single horizontal or vertical line of white cells cannot traverse more than one thick line. Numbers indicate the amount of black cells in that region. If there is no number, there can be 0 or more black cells. Inside each region, all black cells are connected orthogonally. But black cells must not be orthogonally connected beyond the border lines.

486 – Nurikabe.

487 – Snake BY – Draw in the grid a snake, not touching itself, even diagonally. Each outlined region must contain exactly 3 cells occupied by the snake. The regions that contain the head and the tail of the snake are marked by grey color.

P484

P485

P486

P487

# Puzzle No. 469, 470 : Regional Tapa, Regional Snake

I took a week long break from puzzle construction, which was a little “forced”. Now I’m starting again from tomorrow,  and I want to start fresh, so discarding all my “reserve” puzzles and starting new on everything, as I like to do after a break.

The Regional Tapa isn’t that difficult but the Snake is.

Rules –

P469 – Rules of Tapa. Additionally, a clue also indicates the length of shaded cell groups in its region (in the exact configuration as the clue). Some regions may not have clues and have no restrictions. A “?” can stand for any number, but the number(s) needs to be constant for the clue cell as well as the region it is in.

P470 – Find a snake in the grid whose body consists of horizontal and vertical segments. The snake’s body never touches itself, not even diagonally. The head and tail of the snake are not given. Numbers in each of the regions surrounded by thick lines denote the number of cells occupied by the snake in that region.

Enjoy!

P469

P470

# Puzzle No. 453 : Regional Snake

I’m still a little busy, and its looking like that will continue through November. So, I’m just gonna post the puzzles I wrote for team practice before WPC, one by one. I will post write-ups too, somewhere in between all that. As of now, I’m mainly devoting about 5 minutes a day of my schedule to the write-ups, so I’ll fill them in little by little 😛

I decided to post the Regional Snake today. It has, quite literally (!) a narrow solve path. But I still think it uses the regions nicely.

Rules – (copied from the WPC Instruction Booklet, Serbian Round (R7)) Find a snake in the grid whose body consists of horizontal and vertical segments and its total length is 45 cells. The snake’s body never touches itself, not even diagonally. The head and tail of the snake are not given. Numbers in each of the regions surrounded by thick lines denote the number of cells occupied by the snake in that region.

Rated – Hard.

P453

# IPC Preview – Practice, Solving Tips, Links

Update: Fixed the typo in Pentomino Kakuro. New PDF uploaded. No other change.

Update: There is an erratum published on the IPC site that says the 2×2 restriction applies to Happy Dots too. Since the practice puzzle in the PDF still gives a nice practice for placing the dots and forming regions, and only uses 2×2 regions minimally, it stays the same in the PDF. We’re sorry for the inconvenience.

If you’re having trouble with some puzzles, seeing/adding to the discussion in the comments might help. (This also serves as a spoiler alert for those who want to work on the puzzles without help)

Right, took a while, but we’re finally there. If you’re still not aware, the Indian Puzzle Championship will be held on 7th July. Here are our (me and Swaroop) best efforts, with the main goal being to try to help the newer participants.

This PDF features –

1. Practice puzzles for B1, B2, C, D, E2, F1, F2, G2, I1, I2, J1, J2, K1, K2, L1, L2, M2.

2. Beginner-level solving tips for all the puzzles in the set.

3. Solutions to all the puzzles in the set.

4.  Links to other practice material, pattern guides, and other technical tips.

Enjoy!

# Puzzle No. 351 – 366 : Zagreb Open puzzles

I managed to somehow squeeze this set out in one day just before my exams started, right in the middle of the hectic submissions time in college. After that, Vladimir managed to squeeze in some time on that day itself to test these puzzles, so many thanks to him for that.

Rules all placed at the start of the post with the puzzles coming later (Trying a new format for posting, simply because its more convenient for me. The puzzle captions should aid you in knowing which rule is for what puzzle, but the ordering is the same as well, so it shouldn’t be much hassle either way.

Rules –

351 – Akari.

352 – Fillomino.

353 – Graffiti Snake.

354 – Heyawake.

355 – Japanese Sums – Place the digits 1-6 in some of the squares, so that no digit is repeated in any row or column. Sums on the outside indicate the sums of consecutive digits in that row or column, in order. Each sum is seperated by at least one empty square.

356 – LITS.

357 – Nanro – Write numbers in some cells of the diagram. All numbers in a region must be equal. The given number in a region denotes how many cells in this region contain a number (at least one). Same numbers must not be orthogonally adjacent across region boundaries. Numbered cells must not cover an area of size 2×2 or larger. All numbered cells must form a single orthogonally continuous area..

358 – Odd Even Skyscraper – In addition to Skyscraper rules linked to below, all outside clues that are shaded are odd. The rest are even. Range 1-6.

359 – Pentopia.

360 – Regional Yajilin.

361 – Shakashaka.

362 – Skyscrapers. Range 1-6.

363 – Tapa.

364 – Tents – Place a tent ortogonally next to each tree so that no two tents touch eachother, not even diagonally. Numbers on the outside indicate the amount of tents that are in that row or column.

365 – Walls Fillomino – Some region borders are given; i.e. the numbers on both sides must be different.

366 – Yajisan Kazusan.

Enjoy!

P351

P352

P353

P354

P355

P356

P357

P358

P359

P360

P361

P362

P363

P364

P365

P366

# Puzzle No. 344 – 346 : UKPA Open Tournament puzzles

I’d sent many more puzzles for the UK tournament, but the rounds were put together in a bit of a rush, so a lot of them will be used in future contests, I’m told. Anyway, the 3 that were used, 2 Snake variants, and a LITS are what I’m posting now. Its been a while since the Puzzle Booklets were released on the UK forum so most of you have probably seen these. Still, for the few who haven’t…

On a side note, I’ve been working on a few puzzle sets recently too. While a few of these might/might not make it here, one set in particular will sometime in the next week I think. So, something to look forward to.

Also, try out April Contest by Riad on LMI. Its tough, but there aren’t any time constraints, so one can solve the puzzles at their own pace purely for enjoyment.

Anyway, to the puzzles.

No. 344 – Horse Snake – Blacken some cells so that they form a single continuous path, one cell width (the snake), which head and tail are given. The snake cannot touch itself, even at a point. A clue in a cell corresponds to the number of snake cells (head and tail included) which can be reached in a knight step from this cell. There cannot be any snake segment on a cell containing a clue.

P344

No. 345 – Slitherlink Snake – Draw a 1 cell-wide snake of unknown length, not touching itself even diagonally. Its head and tail are marked with circles. The snake cannot go through numbered cells. Numbers show the amount of cells occupied by the snake in the four neighboring cells.

P345

No. 346 – LITS – Colour a shape of 4 orthogonally connected squares in each black bordered region so that all coloured squares form a single contiguous area. This area can’t contain any 2×2 coloured squares. Two identical shapes in different regions can’t touch eachother by a side. Rotations and reflections are considered the same shape.

P346

# Puzzle No. 316 – 336 : Polish Championship set

I’d mentioned a few posts earlier, that I’d contributed some puzzles to the Polish Championships this year. There was an offline qualifier, an online qualifier, the finals, and the playoffs. I think there was a good share of my puzzles in all 4 of these rounds. Its pretty confusing which was used where, since I’ve not organized it that well in my folders, so I’ll just post all the themed ones together (as mentioned in that post linked to above, the online qualifier had puzzles that I used simultaneously elsewhere and were more of a hurried solution).

The theme I was working on should be pretty obvious on seeing all the puzzles. It started with the easier Tapa, which I made completely by accident while writing a bunch of newspaper puzzles, and then I just tried a similar thing with the Corral and that happened quickly too. So, just decided to go along with it, discarded those two from the newspaper bunch and started off the Polish set with them. I couldn’t really try and retry the puzzles to get the exact appearances I wanted, and this is apparent from the 2 LITS and the Killer Sudoku among other ones. The LITS is of course something difficult that I set myself to do in a pretty short timespace, as both LITS were required hurriedly for the qualifiers, and to make it have duplicated regions throughout on the first try seems almost impossible, at least for me.

Anyway, here they are. As with the Zeka set, rules are either linked to by the puzzle names or just added here. These puzzles have varying difficulties, but I don’t think anything was exceptionally hard.

Enjoy!

P316 – ABC Box – Fill the grid with letters A, B and C. The clues outside give the sequence of letters in that row or column. If the clue is a number, that is the number of times a letter appears in that position of the sequence (Which letter is determined while solving). If the clue is a letter then that letter appears in that position of the sequence (The number of times it appears continuously is determined while solving). A “?” means that an unknown letter is appearing an unknown number of times in that position of the sequence.

P316

P317  : Akari.

P317

P318 : Corral.

P318

P319

P320, 321 : Fillomino.

P320

P321

P322 : Heyawacky.

P322

P323 : Killer Sudoku 8×8 – Follow regular sudoku rules. Additionally, the numbers at the top left of a cage gives the sum of numbers in that cage. Numbers cannot repeat in a cage.

P323

P324, 325 : LITS

P324

P325

P326 : Masyu

P326

P327 : Pentasight

P327

P328 : Pentopia

P328

P329, 330 : The Persistence of Memory

P329

P330

P331 : Regional Yajilin

P331

P332, 333 : Tapa

P332

P333

P334 : Tapa Skyscrapers

P334

P335 : Yajilin

P335

P336 : Yajisan Kazusan

P336

# Puzzle No. 272, 273 : A Descriptive Pairs Sudoku and a Descriptive Pairs Snake

Daily League Update :

Earlier today/yesterday, depending on the part of the world you’re in, Tom Collyer shared his contribution for Friday, a Classic Sudoku.

Also, Tom has made a nice document with Week 1’s 4 Sudokus and you can view that pdf here. The pdf also features the best timing from our little group of solvers, and an interpretation from that of the target times for different solvers.

Now to today’s pair. The Snake is small and maybe easy, but I was pretty adamant to get a Snake variant into this series and this seemed to work well. The Sudoku came out nicely and I actually think more can be done with this type. I’d rate it at a medium.

For 272 : Follow regular Sudoku rules. Additionally, for every pair of outside clues X and Y, at least one of these cases is true :

1) X is in the Yth position in that direction.

2) Y is in the Xth position in that direction.

For 273 : Locate a Snake of one-cell width in the grid, that does not touch itself even diagonally. The snake travels in sequence 1-2-3…9-1-2-3…9 and so on. The length of the snake is unknown but head and tail are given.

for every pair of outside clues X and Y, at least one of these cases is true :

1) X is in the Yth position in that direction.

2) Y is in the Xth position in that direction.

Enjoy!

P272

P273

# Puzzle No. 199 : Graffiti Snake

This is the other UKPC puzzle. Refer to my previous post for details. Now, for 200, I haven’t really had time to even think of something. Tomorrow, I have a bit of free time, so will see what I can come up with then, but I wouldn’t expect much. Lets see.  As it is, I’m posting this early as I’m exhausted for the 3rd day running and will probably doze off soon enough.

Anyway,

Rules – Paint some cells black to form a wall. The numbers outside the grid indicate the number of blackened cells in the corresponding direction, in order, as in a Paint by Number puzzle. If there is more than one blackened block in a row or column there has to be a white cell between the blocks. Additionally, a snake must pass through all the remaining white cells, moving horizontally and vertically and not touching itself, not even diagonally. The head and tail of the snake are given as the gray circles.

Rated – Hard? Maybe.

Enjoy!

Puzzle No. 199

By Prasanna Seshadri Posted in Hard, Snake

# Its as easy as IPC (practice puzzles) (Part 1?)

I’m not numbering these simply because I don’t want to rush to 200 as I’m not ready with an idea for that 😛

These are puzzles that can be used for practice for the Indian Puzzle Championship and you can refer to the Instruction booklet provided on that link for better understanding of the rules with examples.. These are mostly around the difficulty I’ve generally seen at IPC, i.e. , around easy for experienced solvers, somewhere from medium to more for the first time solvers.

I’ve concentrated on types that are not on my blog already. You can see previous posts for Masyu, Slitherlink, Tapa, Graffiti Snake here and here.  I wasted a lot of today making a Liar Slitherlink only to find that I’d made a stupid error right at the start. Thats why only 6 puzzles, I hope to have either a Liar Slitherlink, or some other puzzles ready tomorrow, and Friday. Lets hope I get them working 😉

Anyway, obviously the heading suggests what I’m gonna open with.

As Easy As IPC

Enter the letters I, P and C, so that each letter appears exactly once in every row and column. Some cells will remain empty in each row and column. The letters outside the grid show the first seen letter from that direction.

Tapa Borders

Paint some empty cells to create a continuous wall. Numbers in a cell indicate the length of painted blocks on its neighboring cells. If a cell has more than one number, there must be at least one white cell between the blocks. No 2×2 squares can contain only painted cells. The borders between some cells may be thick or non existent. A thick border separating two cells means one is painted and one is not. Lack of a border means the 2 cells are either both painted or both white.

Battleships

Locate the indicated fleet in the grid. Each segment of a ship occupies a single cell. Ships can be rotated but cannot be reflected. Ships do not touch each other, even diagonally. Some ship segments, or sea cells without ship segments, are given in the grid. The numbers outside the grid reveal the total number of ship segments in that row or column.

Note : The letters A, B, C may be equal or unequal, the only constraint I’ve added is that their sum equals 4. This is just to introduce first timers to the summing up logic that can be used sometimes in this type.

Snake

Locate a snake in the grid, whose head and tail are given. The snake does not touch itself even at a point. Numbers outside the grid indicate lengths of snake segments in the corresponding direction.

Star Battle

Place the given number of stars in each row, each column and each region. Stars cannot touch each other, not even diagonally.

Colored Star Battle

I’m new to this type myself even as a solver, so the puzzle may leave a lot to be desired. Sorry about that. Although it should be an easy warm up for first timers, I do think the difficulty of the IPC one will be higher given the high points. Anyway,  Place the given number of stars in each row, each column and each region. Similarly colored stars cannot touch each other, not even diagonally. Some stars may be given.