DJ Ape .Net – The Home of Perfect Sudoku

Here is something brand new, well, for this site anyway: Hanjie puzzles, previously known under the name “Tsunami”.

I have been supplying these puzzles to Euromedia Finland since July who are publishing a Hanjie magazine every month. Each issue of their magazine contains 31 of my Hanjie puzzles in various sizes, from 10×10, 15×15 and 20×20 to 60×80, 100×100 and even 120×80.

These puzzles aren’t Sudoku-related. It’s a logic puzzle with its own rules, which are quite simple:
1. you start with an empty grid and you must paint it so the sequences of numbers on the top and on the left hand side are satisfied.
2. if there is only one number for a row/column, it means that there is only one “patch” of black cells in that row/column. Of course, the number indicates how many black cells there are in that patch.
3. if there are more numbers, they tell you how many patches of black cells there are. Two patches of black cells MUST be separeated by at least one white cell.
4. each row or column can start and end with any number of white cells, including zero.

The trick is that you don’t know how many white cells separate two patches of black cells. However, each puzzle can be solved by using deduction logic only! You do have to count a little and add a few numbers, but that’s all.

When you solve a puzzle, you are rewarded with an image of something. It is usually a portrait of a person or a silhouette of an animal or a sign of some sort. This is why these puzzles are so appealing.

Hanjie puzzles are becoming quite popular these days. I’m looking for a publisher who would publish a book with my Hanjie puzzles. Of course, as any of my other puzzles, Hanjie puzzles are available to newspapers and magazines, too. Just send an e-mail to hanjie@djape.net and tell us what you need. I can produce these puzzles in any size you require.

I will soon start a new website with only these puzzles, but I don’t know when will that be done.

Ok, after all this talk, here is my first sample Hanjie puzzle for you!

Hanjie puzzle (griddlers, pic-a-pix, paint-by-numbers) for September 28, 2006

Download the puzzle by clicking on this thumbnail:

solution – final

Questions? Comments? Suggestions? I’m keen to here what you think!

Well, folks, one year has passed since I posted my first INSANE Killer Sudoku puzzle. Although it wasn’t “perfect” (it contains singleton cages), most probably this site wouldn’t become popular if it hadn’t been for that puzzle. It was by far the most difficult Killer Sudoku puzzle that the world had seen at that time and it still ranks pretty high I would say.

To mark this anniversary, I’d like to post another “unsolvable” puzzle. Actually, according to my ranking formula, it’s the most difficult one that I currently have in my archive. This one is rated 7425379, while Sep 27 2005 puzzle is now rated 6245754 (ratings assigned by PS v0.5).

Warning: This puzzle almost certainly requires trial and error attempts to solve. You might try with the Nobbes’ theory ((c) mikejapan), but don’t be surprised if you can’t place a single number. Although I half-expect that Shai or udosuk, Frank, nd, jc, Ruud (or someone else?) will come back in a few hours and post a 3-step walkthrough.

Killer Sudoku for September 27, 2006 – INSANE

Download the puzzle by clicking on this thumbnail:

solution – final

Here is the content of the data file if you want to import it into PS:
3×3::k:2825:3329:4099:4099:4099:6679:1807:4112:6161:2825:3329:4885:6679:6679:6679:1807:4112:6161:1299:1299:4885:4885:4885:6679:4642:4112:6161:2596:3101:3101:2334:4904:4402:4642:4642:6161:2596:2596:3101:2334:4904:4402:3123:3372:3372:6207:5422:5422:2334:4904:4402:3123:3123:3372:6207:4160:5422:6457:4923:4923:4923:1853:1853:6207:4160:1857:6457:6457:6457:4923:3663:2631:6207:4160:1857:6457:3917:3917:3917:3663:2631:

Have fun!

How many Sudoku variants are there? I don’t know. To calculate, you’d have to multiply the number of overlapping types with the number of variants that impose additional constraints on each puzzle. I produce puzzles with 5 different constraints: Killer, Odd/Even, Greater/Less than, Consecutive, and Non-Consecutive. But then again, you can put an “X” on each of those, so you’d have to double the number. Some creators even produce puzzles that can have more than one of these constraints. Then there are jigsaw sudoku puzzles… Well, I’ll leave it up to you to count all different variants, while I’m presenting you another one for the very first time: Clueless Consecutive Sudoku puzzle!

In this puzzle, there are 9 Sudoku puzzles with no overlapping regions! If you attempt to solve them individually – you won’t get far.

Here is where the “clueless” part comes in: in all of those 9 puzzles, the center nonet is empty. As you plug in your numbers, center nonets (shaded in grey) start filling up. The trick is that those 9 center nonets, put together, also constitute a valid Sudoku puzzle. So, when you run out of ideas, start working on the 10th puzzle and it will give you enough information to solve the whole lot. Those 10 puzzles together have, of course, a single solution.

Important: Consecutive numbers are marked as usual with pipe symbols “|”. Pay attention to lines that separate sub-puzzles: consecutive/non-consecutive cells are marked there, too. However, in the 10th puzzle that consists of 9 nonets from other 9 puzzles, the only (non)consecutive cells are those that are already marked. There is no information given about consecutiveness of the cells between those 9 nonets. I hope you see what I mean.

If you have any doubts about the rules for this puzzle, please ask here or in the forum before you lose a lot of time attempting to solve this puzzle.

Clueless Consecutive Sudoku for Monday, September 25 – this is the only place you can find this kind of Sudoku puzzles!

Download the puzzle by clicking on this thumbnail:

solution – final

It’s been a while since I last posted a Butterfly Killer, let alone one with the “X” factor. So, here it is – and to spice it up a little, I made it quite hard (altho I expect someone to get back in 20 minutes and say it was way too easy).

So, you get 4 of your favorite Killer Sudoku puzzles in this one, heavily overlapped, plus all 8 diagonals must not contain duplicate numbers. Make sure you remember Twin Nonets and Twin Diagonal Triplets techniques!

Butterfly Killer Sudoku X for Thursday, September 21 – IQ – this is the only place you can find this kind of Sudoku puzzles!

Download the puzzle by clicking on this thumbnail:

solution – final

Have fun!

Well, folks, it’s been more than one year since I started posting puzzles on this website and I’d like to write a few words about that. Actually, since this site has become popular thanks to Killer Sudoku puzzles I intended to wait until the anniversary of the first Killer Sudoku puzzle posted here, but CathyW jumped the gun a little too early in the forum on this topic. Nevermind that, here is a brief history of www.djape.net.

It was on September 13, 2005 when I made my first post on this site. The first Killer Sudoku puzzle was posted on September 26, followed by the infamous September 27 puzzle which rightlfully has its own category.

From something that was intended as a pet-project, this site has grown into something quite serious for me. It’s a one-man show as far as programming Perfect Sudoku and webmastering the site are concerned, but the whole thing wouldn’t be what it is without the nice community that you folks have built here. NO website can be successful without regular visitors. So, everyone (except spammers), thanks for making this site possible!

A special thanks also goes to Luis-David Neel from Portugal who was the first person to contact me about publishing my puzzles (the “Sudoku K” book), which sparked others to do the same. My puzzles now appear in books and magazines in Portugal, Greece, Switzerland, Finland, UK, France and so far in two newspapers – The Washington Post and The Washington Express. There are, of course, Sudoku K and The Way Of Samurai books, which are available worldwide.

I will soon launch something new, which is not a Sudoku variant website, but still somewhat related to it.

Also, I guess after one year I owe to those who have been here since the early days something that I don’t particularly like doing – and that is to write a few words about myself. Those of you who have purchased “Sudoku K” have already had a chance to read my short bio.

Anyhow, here it is. My full name is Predrag Stanojevic, but friends usually call me Pedja, which is a common nickname for my first name. DJAPE is just an anagram. I have absolutely no music talent and have nothing to do with DJ-ing. lol… When I built the site, I thought DJ Ape was just an easy way for English-speaking visitors to remember it.

As you are probably guessing, English is not my first language. I’m a 30 year old computer-science graduate from Belgrade, Serbia (actually, a year ago it was still “Serbia and Montenegro” ). I have travelled a bit – I finished my senior year of high school in Philadelphia, USA and have also lived and worked as a computer programmer in Sydney, Australia for two years in 1999 and 2000, so that’s where I learned my English.

Other than computers, I very much enjoy all kinds of sports, mainly volleyball, soccer, skiing and everything related to water: scuba diving, sailing, fishing or just riding a small boat on the beautiful river of Danube which flows through my city. Oh, I nearly forgot – I’m a passionate player of bridge (the card game) and some day when this whole Sudoku-craze allows me to find some time to wrap it up, I will release my bridge-analyzing utility program.

Ok, that’s already too much. I think I’ll have to post a few variant-puzzles in the next few days so this post would be quickly gone from the first page and lost somewhere in the archives.

Cheers!

Someone complained and asked for more new variants and specifically for cons/non-cons puzzles. So here it is – first ever Consecutive Butterfly (4 in 1) Sudoku puzzle.

“Pipes” (“|” symbols) between cells mean that those cells must contain consecutive numbers. If there is no pipe – those cells can’t contain consecutive numbers. This second part of the rule is very important but also easy to forget. All this, of course, in “Butterfly” format, meaning there are 4 puzzles that heavily overlap.

Consecutive Butterfly for Friday, September 8 – IQ – this is the only place you can find this kind of Sudoku puzzles!

WARNING: The puzzle has only 4 givens but it DOES HAVE A UNIQUE SOLUTION. If you find this puzzle too difficult, well, look in the forum to see who asked for more variants and complain to them.

Download the puzzle by clicking on this thumbnail:

solution – final

Good luck and enjoy!

This is just a reminder that today is the day for new Samurai Sudoku puzzles on Sudoku-Samurai.com.

Today’s variety is something extra special – the first ever non-consecutive Samurai puzzle!

Check it out at: www.sudoku-samurai.com/samurai/index.php/non-consecutive-samurai/ and let me know what you think.

I’m posting this article on behalf of CathyW, one of our regular visitors. It’s about solving sudokus and raising funds at the same time for a very good cause

The National Autistic Society (NAS) is calling upon the nation to take part in the first ever NAS Sudokuthon – the world’s largest Sudoku event.

During the week of 9-13 October 2006, thousands of people across the country can help the NAS to raise over £500,000 for UK families living with autism – by completing thousands of Sudoku grids online, at work and at school.

Whether a big Sudoku fan or a complete beginner, the most difficult grids can be completed – by understanding the rules and using a little logic. For people with autism, the world and people in it can seem like a confusing puzzle, for which it is hard to find the right answers. However, with the right support, advice and understanding, people affected by autism can achieve their full potential – and the NAS exists to ensure people affected by autism can achieve this support.

My son has Asperger’s Syndrome which is an autistic spectrum disorder. With a lot of help he is able to attend a mainstream school and will be taking his GCSEs next year. The NAS is a very worthwhile cause and you could help them while playing your favourite puzzle!

By taking part in the NAS Sudokuthon you will help people with autism make sense of the world in which they live – by raising vital funds towards the work of the NAS and providing a lifeline to those affected by autism, their families and carers.

You can take part as an individual or you could get your company or local school involved. Please contact the NAS Sudokuthon Team:

Email: sudokuthon@nas.org.uk
Sudokuthon Hotline: 08456 78 36 58 (SUDOKU)
www.sudokuthon.org.uk