All Questions
Tagged with lights-out optimization
7
questions
6
votes
4
answers
904
views
Flip counters in a grid so that they alternate in color
Beginner puzzle
This puzzle is intended to be suitable for people who are new to puzzle solving.
Clarification: Both experienced solvers and new solvers are welcome to post solutions to this puzzle.
...
- 13.4k
9
votes
3
answers
940
views
Minimum number of flips needed to fully set a binary string
Source: My school teacher, it was just given as a problem statement.
Problem: You are given a binary sequence $S$ of up to $10^6$ bits. You wish to set all the bits in the string to $1$, but the catch ...
- 103
12
votes
4
answers
2k
views
Prime lights out
You start with a 4x4 grid filled with zeroes. If you press a cell then the cell and all its neighboring (horizontally and vertically) cells will have their numbers increased by 1. What is the most ...
- 36.3k
6
votes
4
answers
464
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 ...
- 1,565
6
votes
3
answers
398
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 ...
- 36.3k
6
votes
2
answers
483
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 ...
- 36.3k
11
votes
2
answers
952
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. ...
- 2,968