# Questions tagged [lights-out]

A type of puzzle typically involving a grid of lights, in which the challenge is to get them all to the same state (on or off). The trick is that each light also affects a number of its neighbors, with sides and corners affecting fewer.

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### Is there any easy way to solve this lock puzzle?

https://js13kgames.com/games/lock-puzzle/index.html The link provides an online puzzle game of $16$ tiles in the form of a $4 \times 4$ matrix of which some entries are in the form of vertical tiles ...
1k views

### Board with all 2020s

Zeroes are written in all cells of a $5 \times 5$ board. We can take an arbitrary cell and increase by 1 the number in this cell and all cells having a common side with it. Is it possible to obtain ...
497 views

### Lights out game on a chessboard

Alice and Bob play a game with an 8×8 grid of lights, all initially on. They take turns choosing a light which is on and turning it off, with Alice going first. However, the grid is rigged such that ...
660 views

### Turn on all squares

Take a square grid of size $a\times b$, with all squares being off. You can tap a square, to reverse the state of that square and all squares located in the same column and row as the tapped square. ...
295 views

### Christmas light horror story!

Inspired by stories of strangely behaved Christmas lights here on Puzzling, I feel comfortable now to share my own Christmas light horror story. It all started when I ordered a grid of star lights on ...
283 views

### Putting up the lights

Feeling festive, you decide it's time to put up the lights. You dig out the box and plug a strand in. Uh oh, they are all the same color. This won't work, these are supposed to be multiple colors ...
1k views

### Counter Flipping

A counter flip game is played in the following way: In each move, you can flip an entire row or column Flipping a row or column inverts all the counters on that row or column from $X$ to $O$ or vice ...
912 views

### Flipping coins in a circle

We have a set of N coins that are all placed in a circle. They all have "Tails" as their face up side. The coins are all distinct and have numbers (1,2,3...N) written on them. In each move, ...
418 views

### Name and solution of puzzle to rotate all arrows to same direction

In this puzzle, when you click an arrow, all arrows immediately next to it (diagonally included), as well as the arrow you clicked itself rotate 90 degrees. The goal is to get all the of arrows to ...
835 views

### Will you be the first to get free?

It is your first day in prison and you are approached by a guard having a hunch for puzzles. He tells you that he gives every new prisoner the chance to be freed if they can present him with a version ...
397 views

### How to get the least number of flips to a plastic chips to get a certain figure?

The puzzle is as follows: (Transcription with grammar errors fixed) A game consists of the following: The challenge is to flip the chips in such a way so that they are as in state 2. You start in ...
209 views

### Maximising the number of lit lightbulbs through row-column toggling

You have an $n\times n$ grid, with each cell containing a lightbulb. On a move, you may select a lightbulb, and toggle the state of that lightbulb, and all other lightbulbs sharing a row or column. ...
333 views

### Different numbers in all cells of a 4x4 board

This is a harder version of this puzzle: Different numbers in all cells of a 3x3 board Zeroes are written in all cells of a 4×4 board. Pressing a cell increases by 1 the number in this cell and all ...
443 views

### Different numbers in all cells of a 3x3 board

This puzzle is inspired by this one: Board with all 2020s Zeroes are written in all cells of a 3×3 board. Pressing a cell increases by 1 the number in this cell and all cells having a common side with ...
2k views

### Strategy for Modified Lights out

A friend of mine showed me a variation of lights out that they were interested in, and asked me if it would be possible to solve any given empty grid. This variation involves toggling not just the ...
322 views

### Putting up the lights two

I hope you are familiar with this. Basically Each strand of 20 lights is wired like a 5x4 grid, and each bulb can be either blue, red, purple, or green. However, when you change the color of 1 ...
173 views

### Highest n where an equal number in all cells is (im)possible

Inspired by Board with all 2020s : Zeroes are written in all cells of a n×n board. We can take an arbitrary cell and increase by 1 the number in this cell and all cells having a common side with it. ...
343 views

### Is a game of Knight's out possible?

In lights out, there is a grid of cells (called lights) that can assume two states. All lights start off. You can toggle a given light, and it will automatically toggle its four neighbours. The aim of ...
1k views

### I am struggling with a complex version of the "lights out" puzzle

Hello my fellow puzzlers. I am new to this holy land so if my question is not the kind you people like to solve, I apologize. As some of you may know, there is a puzzle named: "lights out" based on a ...
207 views

### A generalization of the lights-out problem

Look here for the original problem. Let the set $J$ be the set of pairs of positive integers $(m,n)$ with $m\ge n$. Suppose $(m,n)\in J$. Then there are $m$ lights, which they are initially off. ...
243 views

### The combinational switching lights

You have probably encountered the mini puzzle in various games where you have a set of switches and a set of lights (or other triggers), such that each switch "flips" the states of one or ...
145 views

### Fill 5 x 5 grid

In each cell of a 5 × 5 square there is a token that is black on one side and white on the other. Initially all tokens are placed with the white side facing up. On each move three tokens in ...
250 views

### What's the name of this kind of puzzle? [closed]

Link to a video of a the puzzle What is this puzzle called, and if possible, what is the logic behind it? Clicking a square inverts the state of the square and the ones directly adjacent to it, and ...
4k views

### Grid based color changing puzzle

I am trying to identify the minigame used in the game Fontanero (the code for it is here). It consists of a 3x3 grid of squares, and each square is red or green. You can click on a square to invert ...