Sudoku Tips and Tricks

Tips and Tricks: Sudoku Lesson 1.2 Round-Up

2008-06-16T16:30:00.007-04:00

For a different challenge, try The Greatest Maze on the Web

Sudoku Homework Walkthrough, 1.2

Tips and Tricks: Sudoku Lesson 1.2 Round-Up

On the right you'll find the same Sudoku Puzzle #1005 you found in Lesson 1.2, with four yellow squares added with the relevant numbers. Haven't read Sudoku Lesson 1.2? Didn't print out the game board? Would you like to learn about Sudoku Eggs? Before proceeding, go back and check it out here:

How to Play Sudoku: Tips and Tricks, Lesson 1.2

If you reminded yourself to complete a full Sudoku Sweep (see Sudoku Lesson 1.1) after every successful step, you should now begin to make some progress. The next sweep should help you uncover another two numbers, and the following sweep should add three more numbers to your total without forcing you to pull a muscle. Let's see what our Sudoku Puzzle #1005 looks like now:

The black circled numbers indicate the first Sudoku sweeping round; the blue numbers were found during the second Sudoku sweep.

The solution we are posting here is not the most elegant solution; it is the most straight forward. We solved for the original Sudoku eggs, and then completed two Sudoku sweeps without searching for additional Sudoku eggs. However, there are several. If you felt confident enough with your Counting Your Sudoku Eggs skills to follow them through on every step, then we salute you. In later lessons on this site, you will find our solutions relying more and more on the Sudoku Egg method; when that happens, you will be a step ahead of everybody else.

Sudoku Homework 1.2: Proceeding with Sudoku Sweeps

This is the ground-level, the foundation of our Sudoku strategy. Learning the basics will help you solve any Sudoku puzzle, however difficult.

Sudoku sweeps and Counting Your Sudoku eggs - at first these will feel like two different techniques. Soon, however, you will use them both interchangeably without flinching. As you become comfortable with these early methods, we suspect that you will learn to rely on Counting Sudoku Eggs more and more. This is a good thing. Just remember this: when you reach the most advanced puzzles, the Sudoku Sweep will help you keep your Eggs organized without requiring you to muddy up the paper of your Sudoku puzzle. It will remove all the guess work from your gaming.

As usual we separated the following sweeps by color, so take a look to the right. How are you doing? If you have used our method, relying on the basic Sudoku sweep, your board probably looks like ours does. Perhaps we should try to Count Sudoku Eggs instead of attempting another Sudoku sweep. Without much effort, we can identify some potentially attractive Sudoku Eggs. The ninth column has only a single remaining empty square, so let's fill it with a 4. Afterward, the center-right 3x3 box will also have only a single empty square, giving us another easy solution: the number 3.

Now take a look at the second row: two empties remain (4 and 5) and we can easily solve them if we sweep the board for those numbers. Additionally, the center-middle 3x3 box has two empties in a single column (3 and 9). Even though we cannot solve those squares yet, we can use them to sweep the board, allowing us to solve a square in the top-middle 3x3 box (9); and thus another square at the bottom of the column, in the bottom-center 3x3 box (2).

Time Out.

What do you say? You're a short, down-hill jog to the end, aren't you? The question is rhetorical, but the answer is yes. You are nearly done. Perhaps you felt the road was bumpier than the last lesson's path. There's no shame in repeating this lesson. One exercise you might try is this: return to the original lesson and print out a new Sudoku Puzzle #1005. Pretend we didn't find those original eggs. Instead, focus on the seventh column. In that column, there are four empty squares (1,2,7,9). Using the Count Your Sudoku Egg method, you should be able to solve for one of those squares immediately. In the end, your solution will be the same as ours (see below), but your path will look somewhat different. At any rate, regardless of the road you chose, we are providing you with a clean, beauteous solution to Lesson 1.2, Sudoku Puzzle #1005. Where is it, you ask?

The Power of the Sudoku Egg

Right here. Done and done. You're probably feeling pretty good about yourself. Well, you should. Maybe you're asking yourself, "What does Sudoku Tips and Tricks want me to do next?"

Lesson 1.3 will develop the power of the Sudoku Egg. Learning how to manipulate those Eggs into potential solutions will bring you into the higher realm of Sudoku puzzling. Successfully solving Sudoku Lesson 1.3 will earn you some status, too. White Belt no longer. Yellow Belt you shall be.

How to Play Sudoku: Tips and Tricks, Lesson 1.2

2008-06-16T13:35:00.011-04:00

For a different challenge, try The Greatest Maze on the Web

Before Learning Sudoku Tips and Tricks, Lesson 1.2

Once again, make sure you are familiar with the basics of Sudoku and Sudoku puzzle rules. We are jumping directly into Sudoku Lesson 1.2, so we suggest you scan the following links to make sure you are on the right page, that there isn't a better place for you to begin:

1. Sudoku: Rules of the Game
2. How to Play Sudoku: Tips and Tricks, Lesson 1.1

You're in the right place? Good! Let's get to the good stuff:

Tips and Tricks: Sudoku Lesson 1.2

Sudoku White-Belts: on the right, labeled Sudoku Lesson 1.2 - Game 1005 is a fresh Sudoku puzzle for you to consider. We're certain (or nearly) that you've completed How to Play Sudoku: Tips and Tricks, Lesson 1.1. You are acquainted with our Sweeping the Sudoku Board technique, so why not give it a try with Game 1005? Click on the Sudoku puzzle, print it out, and proceed with your Sweeping. Remember two tricks: try to make mental sweeps rather than pencil sweeps; and do your best to trust the technique itself. See how far it takes you.

Adding Power to your Sudoku Method

Once again, please remember that cleaning up the Sudoku board is always the first thing to do when beginning a puzzle, and always the next thing to do when you've successfully completed a different step. Don't worry: this will make more sense as you proceed with these Sudoku lessons.

If you have tried to clean the Sudoku Puzzle #1005 board already, and if you stayed faithful to our method, you may be eying your results rather fretfully. Understood. Brothers and sisters, we feel your pain. After all your hard work, after three rounds of sweeping, you have only uncovered four new numbers. No, there's no point in attempting a fourth round until you've picked up a new Sudoku technique.

So. On your right, you have Sudoku Puzzle #1005 after three rounds of cleaning the puzzle board. Now it's time to add the Counting Your Sudoku Eggs tool to your Sudoku belt.

Counting Your Sudoku Eggs isn't difficult; however, whereas the Sudoku Sweep cashes your paycheck without any overtime work from you, Counting Your Sudoku Eggs greatly benefits from a touch of finesse and some intuition on your part. With that in mind, have another look at your Sudoku puzzle board. Take a minute to locate the 3x3 boxes, and the columns, and the rows, which at this moment have the most numbers already solved.

Sudoku Tips and Tricks gave our puzzle the old eyeball, in search of Sudoku Eggs. Intuition told us that the 3x3 box in the bottom-left of the Sudoku puzzle was a good bet (there are only two empty squares remaining), as was the seventh row from the top (three empty squares remaining). Check out the image on the right if you don't believe us.

Now that we've targeted two baskets that we hope will surrender up Sudoku eggs, what do we do? First, let's consider what information we have:
* In the bottom-left 3x3 box, the two remaining empty squares contain (1,3), in some order.
* The empty squares in the seventh row contain (1,6,7) in some order.

Can we use this information in any way?

Tips and Tricks: Using Sudoku Eggs

Simply stated: yes.

These Sudoku Eggs are the secret to Sudoku success. Right now, we're going to demonstrate only one quick use for your new Eggs. Have a glance over to the right. In the 3x3 box at the bottom-left of the Sudoku puzzle, we determined that those empty squares would one day be filled by the numbers 1 and 3.

Sure, we have no idea which number will go in which square. But we can still use that information, can't we? Let's use that information to help us complete a special Sudoku Sweep. Draw a mental line horizontally through the 1 and 3 across the board, and then complete full board sweeps for each of those two numbers. Remembering that the two empty squares in the bottom-center 3x3 box (again, consult the image to the right) must be filled with either a 1,6 or 7, we can now fill in a brand new shiny number 3 (in the yellow square).

What do you do after every successful step? That's right: do another Sudoku Sweep. And now you're on your way to solving Game #1005. If you make clever use of your Sweep technique AND the Sudoku Eggs in the seventh row from the top, you should be able to solve those three empty squares as well. Give this puzzle a try. DON'T FORGET: AFTER EVERY SUCCESSFUL STEP, DO ANOTHER SUDOKU SWEEP.

Finished? Check your work here:
Sudoku Tips and Tricks, Lesson 1.2 Walkthrough

Bag O' Tricks: Sudoku Links

Tips and Tricks: Sudoku Lesson 1.1 Round-Up

2007-10-06T12:47:00.003-04:00

For a different challenge, try The Greatest Maze on the Web

Sudoku Homework Walkthrough, 1.1

Tips and Tricks: Sudoku Lesson 1.1

On the right hand side (no, the other right, Einstein) of this lesson round-up, we have posted what Sudoku Lesson 1.1 Game # 1001 should look like after one full number sweep. Confused? Haven't read Sudoku Lesson 1.1? Didn't print out the game board? Go back and check it out here:

How to Play Sudoku: Tips and Tricks, Lesson 1.1

You may very well ask, "Sudoku Tips and Tricks Team, why didn't you fill in some of the other obvious squares? Did you guys miss them?" It's true, even the average first-time Sudoku gamer might have solved a square in the bottom-left 3x3 box or the bottom-right 3x3 box, or yadda-yadda-yadda. This is all well and good when you have an easy Sudoku puzzle to solve, such as this one.

It is very important for you to get into the habit of making these sweeps all the time. It is important not only when you are beginning a new Sudoku puzzle, but also after every step you take to solve a particular game. We want you to place your faith in the sweep method whether it seems too easy for you or not. Later, when your Sudoku bag of tricks is heavier and the puzzles you face are more challenging, you will pat yourself on the back for learning the sweep lesson NOW.

Sudoku Homework 1.1: Sweeping After Every Step

You have completed your first full Sudoku board sweep. What should you do now? You should do what you will always do after every step: another board sweep.

You can see where this leads: after every board sweep that delivers a brand new shiny number to your doorstep, you will go ahead and do another board sweep.

Yep. Keep sweeping the Sudoku board until you are no longer turning up new numbers. In the case of this particular puzzle, Sudoku 1.1 Game 1001, you will never get to a point where a board sweep fails to deliver.

Breaking Down Each Sweep

Give it a try. Make sure you have printed out the original Example and then get to it: do a sweep, 1 through 9. Once you have finished with number 9, consider whether or not you solved any new squares during the sweep. If you solved even one tiny new square, go back to the number 1 and perform another sweep. So on. So forth. Keep sweeping until you have done a full sweep without any new solutions.

Once again, as always, for the record: feel free to click on any or all of the Sudoku puzzle images: we will open them for you in a nice clean window. All you need to do is print them.

We have provided full Sudoku board images of every sweep you will need to do: there are only four full sweeps (five, if you count the last). The last image is the puzzle solution.

Please notice the following: even when you restrain yourself from filling in the obvious answers that do not directly link to a board sweep, by the end of your fourth board sweep you will have solved every square on the board, except for three.

. . .

Meditate on that for a minute.

Our board sweep technique asked you to proceed numerically from one to nine, adding only those numbers to the board that followed from a round of sweeping. And after only four sweeps through the board, you have already solved for nearly every square.

The remaining squares are as easy as pie (eating pie, rather than making pie). For all of your hard efforts, we have decided to post a nice, clean solution to Lesson 1.1.

What Comes Next

Once you have the Sudoku sweep down pat, you are ready to move on to Lesson 1.2: Counting your Eggs.

Counting your Eggs is another simple technique that you need to learn early in your Sudoku training. This technique harmonizes beautifully with your Sweeping technique. In fact, Counting your Eggs brings your sweeping broom out of the stone age and into the modern era.

When your Sudoku bag of tricks is heavier, and filled with advanced, awe-inspiring tricks, you will discover that the Counting your Eggs step will come quite naturally to you. Learning these two techniques together puts you on the fast track to Sudoku success.

Ready? Stroll over to How to Play Sudoku: Tips and Tricks, Lesson 1.2

How to Play Sudoku: Tips and Tricks, Lesson 1.1

2007-10-05T16:36:00.001-04:00

For a different challenge, try The Greatest Maze on the Web

Before Learning Sudoku

Before we begin, make sure you are familiar with the basics of Sudoku: puzzle rules, how to play, how to win - yes, those are, basically, the basics. For the benefit of everyone, Sudoku Tips and Tricks has provided you with exactly the bare-bones essentials you need. Go ahead. Check it out. Take your time. When you're ready, please come back and join us in the classroom.

Sudoku: Rules of the Game

Go on, don't be embarrassed. We promise not to tell anyone.

Tips and Tricks: Sudoku Lesson 1.1

Okay, Sudoku white-belts: we are ready to begin. On the right, labeled Sudoku Lesson 1.1 - Game 1001 is an example of a fairly simple Sudoku puzzle. For those of you who studied our Rules of the Game (see above) or have already completed Free Sudoku Novice Puzzles: 1001 - 1002 this example will probably look a little familiar. For the rest, please feel free to give the image a click: we will open the puzzle in a spankingly new, exhilaratingly printable window. Spank and print away at your leisure.

There are as many Sudoku puzzle strategies as there are stubborn knuckleheads in the nosebleed section of Fenway Park - yes, perhaps even more than that. Most average Sudoku gamers usually follow the beat of their own drum: they just plow through the game, trusting to their wits; or worse, with their sneaky pencil they will add a number to the Sudoku puzzle before they have uncovered the solution with 100% certainty. Honest! Some Sudoku gamers will stoop so low as to guess. Don't be distressed. We will teach you our step-by-step method with which you can change the Sudoku world for the better.

Step 1.1: Sweeping the Sudoku Board

Cleaning up the Sudoku board is always the first thing to do when beginning a puzzle. You should also make sure (don't forget!) to clean the board after every future step of our Sudoku method. This is how you do it:

Sweep the board numerically. Imagine that every number 1 is like a tiny sun, whose rays sweep across the board. Mentally sweep horizontal and vertical lines from every number 1 all the way to the edges of the Sudoku board. All of the squares that your lines sweep through are spaces that no other number 1 can live, in accordance with martial Sudoku law.

Pay particular attention to those 3x3 Sudoku boxes that are quite dirty already - those boxes that have many of its squares already filled with other numbers, but are still missing the number 1. Using the Sudoku sweep technique on our example to the right (again, feel free to click and print), you will see that two 3x3 boxes only have one remaining clean square. That square, in each of the boxes, is clean enough to become a number 1.

Now, before we proceed, we want to return to our favorite hobby horse: mental solutions versus pencil solutions. Perhaps you are the dutiful, diligent sort of student who printed out our example when we made the suggestion. Perhaps you have followed along with the lesson by making nice long sweeps with your pencil. At the moment, perhaps, your printout looks something like the cluttered, dirty pencil-sweep example on the right. For shame.

It is very important to get in the habit of doing these sweeps mentally. Please try not to draw on the Sudoku board unless you are writing down a happy, clean number on the grid. Remember: this is only Step 1.1 and we have only uncovered two new number 1s. There simply isn't room for pencil clutter within our Sudoku method. Think how impressed that slob sharing your subway seat will be when you are able to solve the puzzle without soiling your Sudoku pages.

Your first assignment: Using the sweep method, sweep the entire board numerically, all numbers 1 through 9. Try to curb your enthusiasm and use only the sweep strategy. Do not fill in obvious numbers if you didn't sweep them out. Let's see where this leaves us when we're through.

Finished? Check your work here:
Sudoku Tips and Tricks, Lesson 1.1 Walkthrough

Bag O' Tricks: Sudoku Links

Free Sudoku Novice Puzzles 1003 - 1004

2007-10-05T15:33:00.002-04:00

For a different challenge, try The Greatest Maze on the Web

Novice Sudoku Puzzles: 1003 - 1004

Printing Instructions: Simply click on the Sudoku Puzzle Image on the right-hand side of this post. We will open the puzzle for you in a new window, a clean window, a happy Sudoku window without words, suggestions, blather - without anything to distract you except all of those little fuzzies whizzing around your brain. All you have to do is print the Sudoku puzzles. And solve them, of course.

Sudoku Puzzles SOLUTION 1003-1004

Previous Puzzle: Sudoku Puzzles 1001-1002

Are you looking for a different Sudoku Puzzle pair, or trying to understand the madness behind the Sudoku Tips and Tricks Posting System?

Check out the front page of our Free, Easy Sudoku Puzzles contents section.

Solutions: Sudoku Puzzles 1003 - 1004

2007-10-05T15:27:00.002-04:00

For a different challenge, try The Greatest Maze on the Web

Sudoku Puzzles Solution: 1003 - 1004

Printing Instructions: Simply click on the Sudoku Puzzle Solution Image on the right-hand side of this post. We will open the solution for you in a new window all by its lonesome self. All you have to do is print it.

Return to the Unsolved Sudoku Puzzles 1003-1004

Previous Puzzle: Sudoku Puzzles 1001-1002

Are you looking for a different Sudoku Puzzle pair, or trying to understand the madness behind the Sudoku Tips and Tricks Posting System? We are quite mad, but we do have a legitimate system, and we assure you that if we understand it, so can you.

Check out the front page of our Free, Easy Sudoku Puzzles contents section.

Solutions: Sudoku Puzzles 1001 - 1002

2007-10-05T14:50:00.006-04:00

For a different challenge, try The Greatest Maze on the Web

Sudoku Puzzles Solution: 1001 - 1002

Sudoku Index: Free Novice Puzzles

2007-10-05T12:19:00.001-04:00

For a different challenge, try The Greatest Maze on the Web

Easy Sudoku Puzzles

We offer many different levels of Sudoku at Sudoku Tips and Tricks, and all of them are free for the printing. Simply punch the link to the puzzle page you want and click on the Sudoku Puzzle Image or Game Number that catches your fancy. We will open the puzzle for you in a new window, a clean window, a happy window without words, suggestions, blather - without anything to distract you except the puzzles themselves and all the little fuzzies whizzing around your brain. All you have to do is print the Sudoku puzzles. And solve them, of course.

Easy Sudoku Puzzles: 1001 - 1002
Easy Sudoku Puzzles: 1003 - 1004

Sudoku Tips and Tricks: Lessons

Free Sudoku puzzles are great, but Sudoku Tips and Tricks is more than just a trash dump for simple puzzles. We have vision. We have a method; we have a plan. Cackle, cackle. The real purpose here is to offer you the key to our vast, previously unfathomable Sudoku wisdom.

This is you: you would like to learn how to beat the game of Sudoku but you firmly believe you shouldn't have to pay for your lessons.

This is us: Sweet. It's a deal.

Free Sudoku Lessons

The Sudoku Tips and Tricks Puzzle Posting System

Once you have navigated your way to your Sudoku puzzle page, you will notice that we have paired two puzzles together based on their level of difficulty. When you print one puzzle, prepare yourself for two. It's a money and space issue. Good for you, cheap for us. End of story.

We also provide free solutions to every Sudoku puzzle we post. Yes. Free. Solutions are provided on a separate page to avoid accidental cheating. We fully support intentional cheating, but we're sure, or nearly, that you would feel ashamed of yourself if you accidentally glanced down at your Sudoku puzzle and accidentally spied the solution, and then accidentally included that solution on your puzzle without solving it by yourself.

If for some reason you do not see a link to your puzzle's solution, please check the date when we posted your particular game. Occasionally it takes us a day to process the answers.

Good luck, and enjoy!

Free Sudoku Novice Puzzles 1001 - 1002

2007-10-05T11:44:00.007-04:00

For a different challenge, try The Greatest Maze on the Web

Novice Sudoku Puzzles: 1001 - 1002

The History of Sudoku

2007-10-04T12:54:00.001-04:00

For a different challenge, try The Greatest Maze on the Web

Sudoku Origins

The word Sudoku (sū-dō'kū) is a Japanese contraction, suuji wa - dokushin ni kagiru, meaning (more or less) "uncoupled numbers" or "numbers occurring as singles." Ah, the poverty of the English language.

However, the origin of the Sudoku puzzle itself is not Japanese. No: under the name Number Place, Sudoku puzzles were published in a New York-based puzzle magazine, 1979, where they were soundly ignored by every New Yorker alive in the city at the time.

In 1984, Number Place stormed the Japanese coastline like Godzilla surfing in on a tsunami. The popularity of the game was such that the name "Number Place" was scrapped as a bad job and replaced with the excitingly fresh Japanese equivalent of the name "Numbers Occurring as Singles." Very creative. We're very impressed. Very.

The Sudoku Craze

At long last, planet Earth has caught up with Japanese tailcoats. By the year 2005, even New Yorkers were playing Sudoku. You can usually find a daily Sudoku puzzle in your favorite daily newspaper or magazine, but impatient fans tend to buy dime store Sudoku collections or larger compilations found in nearly every single bookstore in the entire world. Yesterday, the Sudoku Tips and Tricks crew even found a Sudoku section at the Used, Rare and Collectible bookstore down the block. No. Not really. But you can see what we are talking about: Sudoko is rapidly becoming a classic.

Thanks to the internet, there are new and plentiful ways to get your hands on Sudoku puzzles, solutions and, yes indeed, lessons to make you a happy, confident black belt master of Sudoku. Many of those plentiful ways are also free. For example, close your eyes and think fanciful thoughts. When you are done, open your eyes and gaze with delight at Sudoku Tips and Tricks.

We are your doorway to Sudoku satisfaction. Every day, or nearly, we are adding new Sudoku lessons to our website, which are yours to read or print absolutely free. In addition, we are making available Sudoku puzzles for all skill levels between the range of Silly Infant and Advanced Guru. Go ahead, print them out and play them all you want. Yes, for free.

Do you have a website? Are you interested in posting something you see here into your own website? We suggest summarizing a paragraph or two and then politely linking directly to the Sudoku Tips and Tricks article post that's got you so excited. We thank you very much for that small courtesy.

Bag O' Tricks: Sudoku Links

Sudoku Basics: The Rules of the Game

2007-10-04T00:14:00.003-04:00

For a different challenge, try The Greatest Maze on the Web

The Sudoku Grid

Sudoku is a number puzzle played on a board divided into a 9x9 grid, and divided again into nine 3x3 boxes, as in Example 1A:

The Sudoku Mission

Your goal is to complete the 9x9 Sudoku grid so that each of the smaller 3x3 boxes contains every number between one and nine.

Sounds easy, huh? Take another look, Speed Racer. While completing each 3x3 box, you must also make sure that every row and every column of the 9x9 Sudoku grid also contains every number between one and nine. If you happen to be counting, you'll realize that there's only room for nine numbers in a given row or column. Nope: no room for extras or doubles.

An Empty Sudoku Puzzle

Example 1B is a reasonably simple example of what an "empty" Sudoku puzzle will look like before you get started:

Yes. The "empty" Sudoku puzzle isn't empty. Count your lucky chickens: every Sudoku puzzle begins with a gaggle of numbers already in place. In general, the easier the Sudoku puzzle, the more numbers you will find already pinned to the Sudoku grid. As the puzzles become more complicated, you will need to dig out a heavy bag of Sudoku tricks to satisfactorily complete your mission.

Take a look at the top row of Sudoku Example 1B. You begin with six of the nine numbers filled in, leaving you three numbers to identify for yourself: you still need the 4, 6 and 8 to complete the row. The first of these empty squares also sits at the top of a column. After some careful examination, you should see that this column already contains the 4 and 8. Therefore you cannot use either the 4 or 8 to fulfill the needs of your row. This, of course, lets you know how to fill that first empty square. Yes, it IS a 6. Very well done.

The Completed Sudoku Puzzle

Your job, of course, is to add numbers to the empty boxes until your Sudoku grid is full and fat, beautiful in every way. For example take a look at this (feel free not to look until you've successfully completed the puzzle yourself, as you like. I'm not the boss of you):

Learning to Solve Sudoku Puzzles

Now that you know the basic rules of Sudoku, it's time to learn how to play. First, you will need to know the smartest way to look at the puzzle board. The next step involves learning simple strategies for locating those empty boxes that are on their knees begging you for a matching number. Once you master these beginner tips, you might want to peek into the intermediate tricks of the Sudoku trade.

Ready to beat the game?
Free Sudoku Lessons

As always, Sudoku Tips and Tricks allows you to print out every Sudoku puzzle you find at our site. Every puzzle is clickable: when you click, we'll open the grid for you in a fresh, printable window. Print free and freely share with your friends. If you post one of our examples somewhere on the web, please credit Sudoku Tips and Tricks with a link on your web site.

Bag O' Tricks: Sudoku Links

World Wide Web Search Page

2007-04-01T20:24:00.001-04:00

Sudoku Search Page