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Just repeat thos three steps for each number that was printed in the puzzle. The purpose of the down, across, and circle marks on each number is to provide for any interruption that may occur when solving the puzzle. By drawling those lines you can always tell exactly where you left off.
If the number has all three marks, you can be sure that all of the corresponding numbers have been eliminated from the puzzle. YOu can effectively forget about that block now. Let's see what the result of all that erasing was. You won't always be so lucky. Not every time will you end up erasing all the numbers but one in a block.
If that is the case, then you peruse the puzzle to find eliminations. First look down each column. If you find a number that only appears in one block in a column. That is the answer for that block. In this picture, the pen point points to a three.
That is the only three in that column, so that must be where it goes. Write it large, then treat it like a pre-printed number.
This isn't thinking. This is EASY. I know, they aren't really quadrants, but you know what I mean, don't you? If you've looked across the columns, and across the rows and there are all duplicates, then look in the group. If there is one number in the group that only appears in one block, then it's your answer. There is no guessing in Sudoku.
One of these situations has to occur. You just need to find them. IN this picture the 5 only appears in one block in the group.
It goes there. Write it big, then treat it like a pre-printed number.
See where we're going, here? I did try it, so now I have to take back what I said about still needing to guess. I tried the hardest puzzles I could find, and the worst trouble I had was having to return to classic solving methods a few times. At one point I made a mistake. Don't know if it was because of the option mapping, but had no trouble getting back on track.This is still tedious, but that can be minimized by solving as much with traditional methods as you can, and only then start mapping solutions. I do want to point out that sudoku programs have tools for this very aid, and that it is considered an aid, not cheating.
It's like setting the program to highlight a given number. Helps you see what to do easier, that's all. First, the word you're looking for is sector.Second, all this writing and erasing is time consuming, but will get you to the end of most puzzles. It's a good way of using what every newbie tries at first, only to end up with a screaming headache. But you made great sense of it. Nicely done.Third, as anyone who has been through an entire sudoku puzzle book can tell you, there is guessing in sudoku, and it definitely helps to have rules for that once you get to the really hard puzzles.So at some point you will want to leave this method behind, grab a pen and pencil, and get to guessing, because the really hard ones give you no choice but to guess. Using a pen makes it easier not to miss the entries you make (when I used a pencil, I kept missing mine and it drove me crazy), and when you need to guess you can reduce each number to a small, unique section of the number.
8, for instance, could by a tiny x in the middle of the square. Make of note of where you start and the number you wrote on the puzzle's edge. If you make it small, you won't make a mess of the puzzle by being wrong. And once you find you are wrong, you can enter the alternatives you now know are correct.Now that you have wrong marks, using the pen to guess will only confuse you. Guess with the pencil, and bear in mind that you can guess as much as three numbers at a time under the right conditions, and it will still be an either or or option.
Certainly a decent way to solve simple puzzles, but make no mistake - solving one sudoku puzzle does not mean solving them all. The above Sudoku puzzle is classified as easy; I can finish it in under a minute without even writing down possibilities. This basic elimination method is generally the last thing you would be doing for intermediate and advanced puzzles. The hardest Sudoku puzzles require a good amount of logical thinking, observation, and occasionally memory. I'd be more than happy to create an advanced puzzle for anyone interested to see if the above method can even fill up a single column, row, or box.
For many who are new to Sudoku puzzles, finding a solution can be a complete mystery. On one hand, with so many numbers, Sudoku seems very mathematical. On the other hand, without the appropriate solution techniques, it can amount to a lot of guessing and checking.In truth, Sudoku puzzles are very well structured and predictable – much like mathematics.Before we cover how to solve Sudoku puzzles, let’s take a moment to review a few aspects of Sudoku including the rules, terminology, and game variations. What is Sudoku?A Sudoku puzzle is defined as a logic-based, number-placement. The objective is to fill a 9×9 grid with digits in such a way that each column, each row, and each of the nine 3×3 grids that make up the larger 9×9 grid contains all of the digits from 1 to 9. Each Sudoku puzzle begins with some cells filled in.
The player uses these seed numbers as a launching point toward finding the unique solution.It is important to stress the fact that no number from 1 to 9 can be repeated in any row or column (although, the can be repeated along the diagonals).Buku Sudoku What Defines a True Sudoku Puzzle?For a puzzle to be a true Sudoku puzzle, it can have one (and only one) solution. There can be no ambiguity in Sudoku. Each number has a single location it must reside in. Otherwise, the player is forced to guess which location to choose thus changing the puzzle into a game of chance.
Sudoku Puzzle VariantsThere are many variations on Sudoku including Mini Sudoku, Cross Sums Sudoku, Killer Sudoku, and Wordoku. We will not cover such variations here. The Rules of SudokuWhile solving Sudoku puzzles can be significant challenge, the rules for traditional solution finding are quite straight forward:. Each row, column, and nonet can contain each number (typically 1 to 9) exactly once. The sum of all numbers in any nonet, row, or column must match the small number printed in its corner.
For traditional Sudoku puzzles featuring the numbers 1 to 9, this sum is equal to 45.This is an important point to review as it isn’t uncommon for inexperienced players to get frustrated and to abandon the techniques we will lay out below. In order to solve Sudoku puzzles reliably, you must be disciplined, focused, and patient. How to Solve Sudoku PuzzlesThere are two main techniques one can use to solve a Sudoku puzzle; Crosshatching and Penciling In.
These two techniques are simple, straightforward, reliable, and sufficient in solving most standard Sudoku puzzles.It is important to understand that all Sudoku puzzles require an iterative approach. Except for in the case of the most simple puzzles, players will have to visit each nonet more than one time. Fortunately, each successive application of the solution techniques yields more completed cells. CrosshatchingTo begin with we will want to use the Crosshatching technique. With this technique, a player considers a single nonet (a single 3×3 square) and attempts to fill in empty cells based on the fact that a number can only appear once in any row or column. By looking across each row and down each column, we can determine if a number can or cannot go in a cell. Let’s look at an example to help illustrate the Crosshatching technique.We will be solving a Sudoku puzzle taken from.
Let’s take a look:In order to understand where we are focusing our puzzle solving efforts, we’ll take a moment to label each nonet, A – I. Getting StartedSudoku puzzles can be started anywhere, but we recommend you begin with nonet A and work alphabetically, left to right, top to bottom.
This strategy helps players remember where they are and where they’ve been.We will follow this advice and focus on nonet A. As there are 5 numbers missing in this nonet (1, 5, 6, 7, and 8), we will make 5 passes, attempting to place each of the five missing numbers in empty cells.
Crosshatching Nonet ABelow you’ll find screenshots of each Crosshatching attempt on nonet A.Crosshatching for 1 (Nonet A)In trying to place the number 1, we cross out all rows and columns that contain the number 1 and pass through the nonet we are focusing on. We’re left with 3 empty cells. As we know guessing is not an option, we’ll move on to the next missing number.Crosshatching for 5 (Nonet A)In trying to place the number 5, we again, cross out all rows and colums with 5 and are left with 3 empty cells. Again, we’ll move on to the next missing number.Crosshatching for 6 (Nonet A)In trying to place the number 6, we’re left with 3 empty cells. By the way, you might not think we’re making progress, but hang in there, such seemingly unproductive efforts are common and more useful than you might think.Crosshatching for 7 (Nonet A)In trying to place the number 7, we’re left with 2 empty cells. An improvement, but this still prevents us from placing the number.Crosshatching for 8 (Nonet A)In trying to place the number 8, we’re left with 3 empty cells.It’s easy to think we’ve made no progress as we were unable to place any numbers in our first nonet. But, don’t despair!
This is very common in Sudoku. You shouldn’t expect to have everything fall into place right away. Some puzzles are straightforward, while others take a bit more time to successfully solve. Let’s move on to nonet B. Crosshatching Nonet BBelow you’ll find screenshots of each Crosshatching attempt on nonet B.Crosshatching for 1 (Nonet B)In trying to place the number 1, we’re left with 1 empty cell. We can place our first number.Crosshatching for 2 (Nonet B)In trying to place the number 2, we’re left with 2 empty cells so we’ll move on to the next number.Crosshatching for 3 (Nonet B)We’re successful in placing 3!Crosshatching for 5 (Nonet B)We’re successful in placing 5!Crosshatching for 2 (Nonet B)We’ve filled in every box in nonet B except one. As such, we know the number 2 must go in the final empty box.If we continue to apply the Crosshatching technique to nonets C through I, we complete our first Crosshatching pass with the following puzzle status.
Penciling InOf course, we could continue to Crosshatch and possibly fill in more empty boxes. However, to best illustrate both Sudoku solving techniques, we’re going to switch to Penciling In.Penciling In is the process of writing down all possible cell candidates in the empty cells of a given nonet.
Then, through crosshatching, we cross off all unqualified candidates. Let’s take a look at how this done.
Again, we’ll begin with nonet A.Penciling In Nonet AIn looking at nonet A, we see we still have the same five missing numbers (1, 5, 6, 7, and 8). We will write all of these numbers at the top of each cell within nonet A as shown below:Once we’ve written the numbers in to each empty cell, we’ll look down each row and column for matches. In the case of a match, we can cross out the matching number in the cell. This is very similar to the Crosshatching we already did, but when considering multiple cells, yields more insight. Let’s look at what numbers we can cross off based on the existing numbers in the rows.Now, let’s look at what numbers we can cross off based on the existing numbers in the columns.We’re able to fill in the 1, 5, and 8 following our Penciling In efforts! Fantastic!Of course, Penciling In numbers effects what can or cannot go in the remaining empty cells.
As such, we take a moment to repeat the Penciling In process for nonet A.Following our Crosshatching and Penciling In efforts, we have completely filled in nonet A and nonet B. We’re really starting to make some progress! Completing the PuzzleRather than continue to, we leave it to you to apply the Sudoku solving techniques we’ve discussed and illustrated to complete the puzzle.To help you, we’re including the completed puzzle below so you can check your final solution.
Remember, true Sudoku puzzles have one (and only one) correct solution. If your final work doesn’t match what you see below, we encourage you to go back and double-check your work.For more puzzle solving fun, we encourage you to visit our page.Tags.