Tips and Tricks: Sudoku Lesson 1.1 Round-Up

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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

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