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Questions tagged [grid-deduction]

Puzzles such as Sudoku or Kakuro, where the final state of a pre-existing grid must be deduced logically through clues placed within and/or around the grid. For puzzles where you are given a list of clues which can be used to compose a grid to solve them logically, use the [logic-grid] tag instead.

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7
votes
2answers
808 views

Fill numbers to the star shaped puzzle

Fill in all the blank circle with numbers 1 to 6, so : Each lines of 6 circles, contains 6 different numbers. Each corner (consist of 3 greens circle) sums to 11. There is only 1 unique solution.
7
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2answers
298 views

Quick Yajilin Puzzles: Scatter and Gather

Yajilin (adapted from Nikoli) Draw a line to make a single loop. Lines pass through the centers of cells, horizontally, vertically, or turning. The loop never crosses itself, branches off, ...
7
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2answers
285 views

Quick Slitherlink Puzzles: KPK and 123

Slitherlink (taken from Nikoli) Connect adjacent dots with vertical or horizontal lines to make a single loop. The numbers indicate how many lines surround it, while empty cells may be ...
7
votes
2answers
208 views

Which number goes in the square with the question mark?

My friend, who loves puzzles as much as me, gave me this image this afternoon. My friend game me a hint: Skyscraper, which, as Daniel Mathias pointed out in the comments, is a type of grid puzzle.
7
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2answers
303 views

Toroidal Heyacrazy: Rainstorm

This is a Toroidal Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the ...
7
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2answers
227 views

Heyacrazy: No Diagonals

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...
7
votes
1answer
630 views

IBaNTsJTtStPMP! #2

IBaNTsJTtStPMP means "I'm Bad at Naming Things, so Just Try to Solve this Patterned Masyu Puzzle!". The original Masyu rules apply. Make a single loop with lines passing through the ...
7
votes
1answer
145 views

What's the next step in this Unequal (Futoshiki) puzzle?

I'm currently stuck on this puzzle from Simon Tatham's website (he calls it "Unequal", although the standard name according to Wikipedia is Futoshiki). My progress so far is: I've even tried a few "...
7
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2answers
278 views

Nono-cube - Ultimate Puzzle Giant

Prologue - Instructions Shamelessly copied and pasted the following from @jafe's puzzle :P This is a three-dimensional nonogram. The first square gives the enumerations for the Z-axis, top to ...
7
votes
1answer
690 views

Can you solve this nurikabe puzzle?

Here's a nurikabe for you. Let's see who can solve it first.
7
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1answer
135 views

Quick Nurikabe Puzzle: $4$s

Nurikabe (taken from Nikoli) Fill in the cells with black under the following rules. You cannot fill in cells containing numbers. A number tells the number of continuous (adjacently) white ...
7
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1answer
193 views

Nurikabe: Sixes

This is a Nurikabe puzzle. The goal is to paint some cells black so that the resulting grid satisfies the rules1 of Nurikabe: Numbered cells are white. White cells are divided into regions, ...
7
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1answer
193 views

Nono-Cube: Approach at Your Own Risk

Inspired by jafe's 3D nonograms :) Answer is one word. This puzzle is a part of Ooohh, it all makes sense now! :D
7
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1answer
371 views

Latin square puzzle

This is a sudoku-esque puzzle I came up with when trying to solve some harder sudoku. The rules It’s a Latin square like sudoku, so there must be the numbers 1-9 exactly once in every row and ...
7
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1answer
165 views

Heyacrazy: Dissection

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...
7
votes
1answer
301 views

(4 of 11: Hitori) What is Pyramid Cult's Favorite Fruit?

Dear PSE users and moderators, I’m new here in PSE, but I really need your help. There was this person who gave me a black envelope consisting 10+1 pages of puzzles, and also a scribble saying: “Find ...
7
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1answer
481 views

Two Christmas trees

To each Christmas tree : Put two $+$, two $-$, and two $×$, to the yellow triangles. in a row, there must be different operators (so between $[2,0,1,7]$ all $3$ operators must appear) $A - B$ means $|...
7
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1answer
404 views

Skeleton sudoku, the second

I've already set one skeleton Sudoku. Here's a rather harder one. (Nonetheless, it should be within the realms of what can be done by hand; I solved it manually myself to verify that there was only ...
7
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2answers
453 views

Making a grid deduction puzzle

When making a grid-deduction puzzle, what are the strategies in making it? For most grid-deduction puzzles, simply putting numbers/dots/whatever in the grid simply doesn't cut it. However, sometimes ...
7
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1answer
268 views

(9 of 11: Shikaku) What is Pyramid Cult's Favorite Stationeries?

Dear PSE users and moderators, I’m new here in PSE, but I really need your help. There was this person who gave me a black envelope consisting 10+1 pages of puzzles, and also a scribble saying: “Find ...
7
votes
1answer
183 views

Color Star (Semi - Instructionless Sum - Star)

Color Star - a semi-instructionless variation of Sum Star Known Rules of Sum Star Fill cells with numbers and shade all remaining cells such that Each dodecagon contains the numbers 1-9 exactly ...
7
votes
1answer
199 views

Latin Square Puzzle - Difficult

Follow on puzzle from the introductory Latin square puzzle post. The rules It’s a Latin square like sudoku, so there must be the numbers 1-9 exactly once in every row and column. Notice that each ...
7
votes
1answer
861 views

Solve this Subtraction sudoku!

This is subtraction sudoku. The rules are basically the same as common Sudoku, but with a few additions. In the row, the number in the orange box is the difference when its left side (sum of 3 ...
7
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3answers
513 views

Slitherlink the second

Find the solution to this slitherlink puzzle that I came up with: This one's even smaller!
7
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1answer
354 views

Slitherlink - It's all in the 2s

Can you solve this Slitherlink puzzle that I came up with? And in CSV: 3 - 3 - 2 - - 2 - 2 - 2 - - 1 1 2 2 1 - - 2 - 2 2 - - - 2 - 1 2 - - 1 - I tried to ...
7
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2answers
255 views

Square Spin #2: Climb the Mountain!

Square Spin History: #1>#2 New Rules This puzzle introduces two new square types: Unmovable squares (Un) Replaceable squares (Re) Plus the concept of ambiguity! ...
7
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1answer
281 views

Connected circles which sum of any two of them which are adjacent is a triangle numbers

Arrange numbers 1 to 36 to the small circles and ovals, with rules: sum of any two of them which are adjacent is a triangle numbers. The first 12 Triangle numbers are 0, 1, 3, 6, 10, 15, 21, 28, 36, ...
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2answers
400 views

3D Statue Park: U shapes

This is a three-dimensional Statue Park puzzle.1 The five squares in the below image depict the five levels of a $4\times4\times5$ cuboid. The goal is to fit inside it the four three-dimensional ...
6
votes
4answers
1k views

Filling the board with 0s and 1s

You are given a $9\times9$ grid board. You have 40 "$1$"s and 41 "$0$"s. You can put these numbers wherever you want on the board. After that, you will take the sum of the numbers in each row and ...
6
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2answers
327 views

Swap — A Puzzle I Created

This puzzle is called Swap. Let's find out why! Suppose you are given a random $\rm N\times N$ matrix (grid) with all the integers from $1$ to $\rm N^2$ each belonging in every grid square (a.k.a. ...
6
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2answers
554 views

Cairo pentagonal tiling logic grid (Edit : with more clues)

Rules : Fill with numbers from 1 to 13, and each number can appear max 4 times. Small numbers between 2 cell shows the difference between the cells. A + D = B + C Example : (In this example, I fill ...
6
votes
1answer
341 views

A symmetrical Yajilin

Inspired by @Athin's efforts, I decided to try to come up with a Yajilin puzzle of my own for your entertainment and amusement. Rules (shamelessly stolen from @Athin's post) Draw a line to ...
6
votes
1answer
398 views

Heyacrazy: Empty Space

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...
6
votes
2answers
384 views

How does one go about creating a new grid-deduction puzzle?

The grid-deduction tag covers puzzles like Sudoku, Kakuro, etc. where the goal is to fill in a grid of numbers [/letters/colours] in a unique way by logical deduction from some predetermined rules and ...
6
votes
1answer
455 views

Hashiwokakero Puzzle

Rules: Connect islands (the circles with numbers) with as many bridges as the number in the island. Bridges can go only in a straight line horizontally or vertically. There can be no more than two ...
6
votes
1answer
442 views

ASCII Art Painting

I've been taking an art course recently, and I met someone who was proficient with grid ASCII art paintings. However, the teacher of the class always seemed to think there was something wrong with his ...
6
votes
2answers
193 views

Quick Shikaku Puzzle: Stars and Stripes

Shikaku (taken from Nikoli) Divide the grid into rectangles with the numbers in the cells. Each rectangle is to contain exactly one number and it's showing the number of cells in the ...
6
votes
1answer
301 views

3D Statue Park: Daggers and dashes

This is a three-dimensional Statue Park puzzle.1 The five squares in the below image depict the five levels of a $5\times5\times5$ cube. The goal is to fit inside it the eight pieces shown in the ...
6
votes
1answer
151 views

Heyacrazier: Big Three

This is a Heyacrazier puzzle, a variant of Heyacrazy. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally ...
6
votes
2answers
141 views

Yajilin minicubes: the Poppycock, the Balderdash, the Gobbledygook

These are three-dimensional yajilin puzzles. In each puzzle, the four squares depict the layers of a $4\times4\times4$ cube. Shade some cells on each layer. The numbered cells show how many ...
6
votes
1answer
234 views

3D tetromino placement

The following image depicts a $5\times5\times5$ cube. Insert any number of the pictured 3D-tetromino pieces into the cube to satisfy the conditions listed below. Pieces may be rotated in any direction....
6
votes
1answer
186 views

3D nonogram – The one-thousander

This is a three-dimensional nonogram. The first ten squares depict the layers of a $10\times10\times10$ cube. The final square gives the enumerations for the Z-axis, top to bottom. Some rules: If a ...
6
votes
1answer
303 views

My featured entry

Mosaic is a Minesweeper-like puzzle based on a grid with a pixel-art picture hidden inside. Using logic alone, the solver determines which squares are painted and which should remain empty until the ...
6
votes
1answer
61 views

Double feature: Unpopular

This puzzle is part 9 of the Double feature series (first part here). The series will continue in "Double feature: Health shakes". Across 2. A victory is found in path leading to hardship (...
6
votes
1answer
111 views

Ambitious Puzzler's Masyu

Contrary to the lazy puzzler, the creator of this masyu is too ambitious that he adds not only one but two extra stones, so the puzzle is unsolvable. Finish his job for him by removing those ...
6
votes
2answers
209 views

You Sign Me Right Round (Extended Edition)

I wanted to ask more questions about variations on This Problem. If you hadn't seen that one, check it out. It's required reading (and probably more fun). In the original problem, these were the ...
6
votes
1answer
197 views

Academic Snake Pit

One day, you get lost in the corridors of your new school and accidentally wander into a pit full of venomous snakes. Unfortunately, the pit is deep and you have hurt your leg in the fall, so there is ...
6
votes
1answer
146 views

The Terrible Twos of Slitherlink Part Deux

Please read and understand my first question before proceeding. This one should be worse. pdf files I uploaded to Dropbox: Slitherlink of Twos Their solutions These puzzles were generated by ...
6
votes
1answer
153 views

Double feature: Going postal

This puzzle is part 8 of the Double feature series (first part here). The series will continue in "Double feature: Unpopular". Rules of Yajilin1 Shade some cells in the grid. The ...
5
votes
2answers
673 views

Incomplete Word Rectangle

This is an incomplete word rectangle: When completed, every row will contain a common English word with four letters, and every column will contain a word with five letters. All of these are common ...