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Algorithmics of sudoku Sudoku puzzles are designed to be solved by human players with pencil and paper but with well defined algorithms , it is possible to be solved in almost real time by computer or even smartphone. A standard Sudoku puzzles contains 81 grids which consists 9 grid rows and 9 grid columns. Sudoku have 9 non- overlapping zones which each zones consists of 3 grid rows and 3 grid columns. Techniques[edit] Backtracking[edit] Backtracking algorithms is adapted to solve the Sudoku that iterates all the possible solutions for the given sudoku. Below is the general pseudocode of backtracking algorithm for standard sudoku template (9x9) [2] Exact cover[edit] Sudoku may be described as an instance of the exact cover problem. Brute-force algorithm[edit] Some hobbyists have developed computer programs that will solve Sudoku puzzles using a brute force algorithm. Advantages of this method are: a solution is guaranteed (as long as the puzzle is valid)solving time is mostly unrelated to degree of difficulty

J History[edit] Use in English[edit] In English, 'j' most commonly represents the affricate /dʒ/. In Old English the phoneme /dʒ/ was represented orthographically as 'cg' or 'cȝ'.[5] Under the influence of Old French, which had a similar phoneme deriving from Latin /j/, English scribes began to use 'i' (later 'j') to represent word-initial /dʒ/ of Old English (for example, 'iest' later 'jest'), while using 'dg' elsewhere (for example, 'hedge').[5] Later many other uses of 'i' (later 'j') were added in loanwords from French and other languages (e.g. 'adjoin', 'junta'). The first English-language book to make a clear distinction between 'i' and 'j' was published in 1633.[6] In loan words such as raj, "J" may be pronounced /ʒ/ by some speakers. In English, 'J' is the fourth-least-frequently used letter in words, being more frequent only than 'Z', 'Q', and 'X'. Use in other languages[edit] The letter J is generally not used in the modern Celtic languages and in Galician, except in loanwords.

Finally, a Definition of Programming I Can Actual I believe very strongly that a blog without comments is not a blog. For me, the whole point of this blogging exercise is the many-way communication of the comments -- between me and the commenters, and among the commenters themselves. As I said in How To Advertise on Your Blog Without (Completely) Selling Out: It's an open secret amongst bloggers that the blog comments are often better than the original blog post, and it's because the community collectively knows far more than you or I will ever know. Indeed, the best part of a blog post often begins where the blog post ends. A blog without comments is like Amazon without user reviews. Comments aren't the only form of commentary on a blog post. Of course, as with all other useful things, there is a dark side to comments. I scrutinize every comment, and I remove a tiny percentage of them: they might be outright spam, patently off-topic, or just plain mean. Comments mean additional work for the blog owner.

Sudoku Cel mai dificil Sudoku din lume Un matematician finlandez sustine ca a facut cel mai dificil Sudoku din lume. L-a realizat in trei luni, si are doar o singura solutie. Pentru rezolvarea acestui puzzel, publicat de abcnews.go.com, sunt necesare cateva deductii logice si incercari alternative. Autorul, sustine ca, desi acesta este cel mai greu Sudoku creat pana acum, cu siguranta vor aparea si alte variante chiar mai dificile de atat. Numarul combinatiilor posibile este, practic, infinit, asa inca nu exista un Sudoku care sa nu poata fi rezolvat, desi unele dintre acestea sunt cu adevarat foarte grele. Incearca si tu acest puzzel. Daca te pierzi si esti decis sa abandonezi, sau daca doar vrei sa te verifici, AICI este raspunsul. mai mult Sambata, 30 Iunie 2012, ora 22:05 1 comentariu Slabeste facand Sudoku! Daca te gandeai cum sa slabesti fara sa te ridici din fotoliu, Sudoku sau cuvintele incrucisate reprezinta solutia, pretind cercetatorii. Miercuri, 25 Noiembrie 2009, ora 11:09 2 comentarii

Learning Contents >> << Usr Pri JfC LJ Phr Dic Rel Voc !: Help Learning J J software and documentation are available at the J Software Home Page This book is also available in various formats from here Please send comments and criticisms to the J Forum Copyright © Roger Stokes 2013. This book is meant to help the reader to learn the computer-programming language J. My hope is that the book will be useful to a wide readership. The scope of this book is the core J language defined in the J Dictionary. Hence the book does not cover topics such as graphics, plotting, GUI, and database covered in the J User Guide, nor does it cover the J Application Library . The book is organized as follows. All the examples have been executed with J701. Acknowledgments I am grateful to readers of earlier drafts for encouragement and for valuable criticisms and suggestions.

Sudoku Sudoku, pronunțat [sudoku], din japoneză 数, sû, cifră, și 独, doku, unică, este un joc în formă de grilă inventat în 1979 și inspirat de pătratul latin și de problema celor 36 ofițeri a lui Leonhard Euler. Scopul jocului este de a umple această grilă cu cifrele de la 1 la 9 respectând anumite condiții, cu unele cifre fiind de la început dispuse în grilă. Prezentare[modificare | modificare sursă] O grilă 9×9 de Sudoku (apăsaţi pe imagine pentru a vedea soluţia, care apare mai jos) Grila jocului este un pătrat de nouă pe nouă căsuțe, subdivizat în tot atâtea pătrate identice, numite regiuni (vedeți figura). Cifrele nu reprezintă decât o convenție, relațiile aritmetice între ele nefiind de nici un folos. Interesul jocului consistă în simplitatea regulilor sale și în complexitatea soluțiilor sale. Acest joc a inspirat deja mai multe versiuni electronice care aduc un interes diferit rezolvării grilelor Sudoku. Grilele sunt publicate în ziare, dar pot fi și generate cu ajutorul unui computer.

Whatever Happened to APL? Late, great Ken Iverson Whatever Happened to APL?by John C. Dvorak (originally appeared circa 1998) The first language I learned to code should have been FORTRAN. APL, was invented by Ken Iverson from 1957-1960 and means, simply, A Programming Language, although it was originally dubbed Iverson Notation when Iverson developed it at Harvard. APL has a number of interest characteristics in its original form. One other noteworthy feature is the power of computation that can be compressed into a single line of code. Some of the drawbacks to APL were corrected by the newer version of the language simply called “J.” — also developed by Iverson with Roger Hui. Doing a Whatever Happened to APL (or J) is somewhat ludicrous because nothing ever happened to the language. APL was a small player during this change over and pretty much got shoved aside completely, which is probably good for the language. This may change with the introduction of two products. Enter J. [note: Ken Iverson died in 2004]

Main Page J Forums The J forum mailing lists give life to the J community. They are the best way to get help, help others, report bugs, and share your interest in J. Newbies ask questions and get helpful, polite answers. Gurus present insights, sample code, problems, and solutions. The programming, beta, source and general forums are core forums. The chat forum is an open discussion group, covering computer languages as long as there is some connection to J: array programming, aspects of other computer languages, historical tidbits, random questions about J, wish lists, etc. The core forums are moderated and posters of inappropriate messages will be directed to chat. Jsoftware will remove any member that, in Jsoftware's sole opinion, sends messages that are abusive or inappropriate to the purpose of the forum. Many people will see your message. In answering questions, remember that teaching fishing is better than giving a fish. Please note that the forum email addresses are the name @ jsoftware.com.

Solving Sudoku : Technique 7 : Hidden Pairs/Triples Hopefully you've got the hang of finding Naked Pairs and Triples - if not, practise looking for those before trying to understand the hidden equivalent! Hidden pairs and triples are quite a bit trickier to spot - they're hiding after all! Using the same notation as before, just looking at the cells which haven't been fixed yet: {46} {24} {13} {26} {123} Because 1 and 3 can only exist in two of those cells (no other cells will accept either of them), that means they must be in those two cells, leaving no room for any other. Even though you don't know which is a 1 and which is a 3, you do know that the two isn't welcome, so you can remove it as a candidate from the end cell! (The eagle-eyed readers will spot that you could have arrived at the same result by looking for the naked triple {46} {24} {26} - which would result in just the same - removing the 2 as a candidate from the end cell. This happens quite often!) Looking for hidden groups Even harder... The elusive Hidden Quad?

Sudoku Generator Sudoku Generator Here is a free Sudoku generator that can generate puzzles of varying difficulty in PDF, Postscript, plaintext, and HTML. It is a nice example of the website fun you can have with 250 lines of Python over a Labor day weekend; it also makes a handy command-line Sudoku solver... Update: For Google Chrome users, try installing this Chrome Sudoku Web App for hints and more. Preview the Sudoku Helper here. What is Sudoku? Have you ever played Sudoku? The rules of Sudoku are simple: finish filling in the squares of a 9x9 grid so that the digits 1-9 appear exactly once in each of the nine rows, columns, and 3x3 blocks. Ways to Play Sudoku is a good solo game; if you are having trouble getting into it, you can read about various solution strategies on the web. But, like crosswords, it can be even more fun to work Sudoku puzzles together with somebody else. I realized Sudoku was a major phenomenon when I saw the Dora Sudoku books for preschoolers. Counting Sudoku Boards Rating Puzzles

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