# Tag Info

## Hot answers tagged grid-deduction

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@Jay already found the solution to this, but I wanted to expand a little more on why it's the only solution:

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Most Sudoku puzzles published have only one solution. If there is more than one solution, it is probably a mistake. That said, puzzles with incomplete clues can have multiple solutions. In the extreme case, a puzzle with no clues has 6,670,903,752,021,072,936,960 solutions according to Wikipedia. I don't know if it's possible to have exactly 3 solutions, ...

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Partial solution

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I'd like to add a simple, direct proof:

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The solution is: or, in text form: Explanation (not the fastest way, I realized some improvements while writing it):

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This seems to fit: The initial step was to replace all 1's (red) with a 2 (black) and all 9's with an 8: Then, whenever a red number was +/- 1 of a black number which was on the same row, column or box, the red number was changed to its other possible value. E.g. if a red 6 was on the same row as a black 5, the red 6 was changed to a black 7 as it couldn't ...

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Final solution Step by step deduction Firstly, note that MASTERING is a full nine-letter word so it takes up a whole row, and EMIGRANT is an eight-letter word so the column is either EMIGRANTS or SEMIGRANT. Also note that ARTEMIS must begin from either the 1st or 3rd place in its row, because otherwise the A will clash with MASTERING; and the remaining ...

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I have been asked by a couple of people to show the creation process for this puzzle, so here we go: Also if people want to see more of these strange, Sudoku mash ups then I'll be more than happy to combine some new types :) Wrap-up: The Making Of This Samurai Pseudoku This is not a solution to the puzzle, but provides notes from its poster. This type of ...

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The completed dish The reasons why The ultimate message Follow the directions My answer

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For the sake of completeness, there are actually 3 possible solutions. Using process of elimination and deduction can get you to this point: One solution is given by Sid already: But two more are: and:

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Well so you could do Full solution (The "Try it online" link agrees that this is legal)

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Kakuro is a type of puzzle that is better created using a bottom-up process, in which you specify one or two sums at a time and explore the logical implications of those moves. Take a look at this list of combinations for 3 cells: 6: 123 7: 124 8: 125 134 9: 126 135 234 10: 127 136 145 235 11: 128 137 146 236 245 12: 129 138 147 156 237 246 345 13: 139 ...

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First, we want to take a look at the snake itself. Then, let's take a look at the grid, and see if there are some obvious features. So, let's fill those in: Then, because the snake has more white near the tail end, I thought it would be a good idea to go from the 93 to the top side as soon as possible; the grid seems to have more white along the right and ...

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First, the Fillomino should be solved: Then, And finally:

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What a fun puzzle! Green means a note. Blue means an important deduction. Red means can be deduced by shallow sudoku logic, or shallow slope logic (I.e. If you have a 1 and 3, a 2 goes in between.) Start off by focusing on 1s and 8s, because they're limited in where they can go (they have to be in a corner). In particular, that top middle area let's us ...

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Here's the solution: I will provide the explanations within the next 24 hours because now I have to go to bed.

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The next part of this puzzle can be found at: How I got this: So, what to do next:

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Answers: Large rodent native to Central and South America (6) Wading bird sacred to the Ancient Egyptians (4) Shrek, Shaun or Dolly? (5) Feathers McGraw, Chilly Willy or Pingu? (7) Captain Nemo's submarine in Jules Verne's Twenty Thousand Leagues Under the Seas (8) Shakespeare play, The Taming of the _____ (5) Favourite food of Obelix in the Asterix ...

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Some quick terms I should define: 'Number chasing' - a strategy similar to sudoku where you focus on a single number, and figure out where that number must appear in some region. Can be applied to place many of the same number around the grid, or to fill out a region totally. 'Can't be anything else' - focusing on a single cell, and working out the only ...

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I have seen two dissenting opinions on this subject (and in my opinion, the first option is right): By definition, a Sudoku has only one solution. Anything else is just a grid of numbers. Sometimes, there are errors in a publication, and a starting grid has multiple solutions, but, then the starting grid was not a Sudoku! From Wikipedia: The number of ...

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Final solution Step-by-step explanation In each of the 2x2 boxes with determinant 0, we have four numbers $a,b,c,d$ between 1 and 9 such that $ad=bc,a\neq b\neq d\neq c\neq a$. This leaves surprisingly few possibilities: The only possibilities for the pairs $\{a,d\},\{b,c\}$ (unordered in all ways; these are just two pairs with equal products) are: {1,9},...

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Armed with Thomas Blue's star-finding work, we may solve the 4 logic grids as follows: The rules of the puzzle Step by step solution: Grid 1 Grid 2 Grid 3 Big grid Here begins speculation

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Okay. THAT. WAS. INCREDIBLE! It took me two solid hours of work to solve and even longer to write and draw it all up here - hopefully it'll be worth it! To start us off, here is the final maze layout and routes: In the following explanation all colours have been abbreviated to their initials as follows: G=Green, O=Orange, P=Purple, Y=Yellow. An ...

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MASSIVE SPOILER ALERT, DO NOT LOOK UNLESS YOU REALLY HAVE GIVEN UP Full solution. No words needed. (Hopefully there are no mistakes) Plus, the lines and text were fully hand-drawn for those of you who still appreciate hand-drawn art stuff. I seriously doubt that anybody is actually going to try reconstructing my solution, but if you have any parts that ...

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Part 1 The final solution (finally)

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Transmission from the moon radio-station After a long time in space I started to forget what N and E stand for on Earth. Well, now it's clear to me: East and North are directions. The first time I tried to get through those Space Grids, I mixed them up and also tried to take clues from the spectrum... Oops, let me get the spoiler glasses on. I might talk ...

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From some lines of the poem: we can figure out that Turns out there's exactly one way to do this. And now, the sequence:

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