故宫博物院召开三年藏品清理工作总结会 藏品总数...
百度 确定没人发现后，他便联系卖家，装作一副受害者的模样，找卖家索赔。
A puzzle based on combinatorics, which is the study of counting discrete structures. Use with [mathematics]
876 questions
10
votes
3
answers
676
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Snow White and the Seven Rooks on Dark Squares
With the white queen on a light-coloured square of your choosing, can you place 7 rooks on the dark squares of the chessboard so that no piece attacks another?
In the above Lichess illustration (with ...
- 82.9k
19
votes
3
answers
678
views
Can I succeed in appraising the candies according to my daughter’s preferences?
My daughter has always been very picky when it came to food. Initially, I thought she made random choices, but after observing this for a while, I found a pattern in her preferences. Let me explain.
...
- 12.4k
8
votes
2
answers
640
views
Create a Distinct 5x5 Grid Using Only 3x3 Increments
This is a follow-up question to Different numbers in all cells of a 3x3 board v2
Here is the playable version.
You have a 5 × 5 grid whose entries all start at 0. A legal move is:
Select any 3 × 3 ...
- 33.1k
12
votes
3
answers
533
views
How many IKEA train track layouts with self-intersections?
Recently, I got an IKEA LILLABO train set for my daughter. It has twelve curved segments, each is 1/8th of a circle of radius 1, two straight segments of length 1, and a bridge of length 2 (in top ...
- 12.4k
2
votes
0
answers
132
views
Which station is my Uncle's restaurant? - Where's Wally? remix in Paris Subway
Finding my uncle's restaurant station on the Parisian RATP subway is a little like "Where's Wally?"
You are given the next Paris' subway map. Please click on it or here to obtain a zoomed ...
- 7,888
14
votes
3
answers
1k
views
The Royal Relay on a Chessfield
Playable Version
In the ancient Kingdom of Gridoria, a mysterious curse has frozen the entire realm: every citizen, every castle, every mountain.
The royal court's only hope lies in a sacred Relay ...
- 33.1k
18
votes
1
answer
1k
views
Double double coil trouble
If you find it tedious and annoying to coil up a garden hose after use, well, you've come to the right place.
Here's a nice quotation taken from a poem by Amy Woolard:
...
- 14.6k
6
votes
1
answer
544
views
The Drunken Bishopawn’s Staggering Tour
Here’s an original version of the puzzle: this question.
Once upon a time, there was a Bishopawn: a hybrid chess piece that moves like a bishop (freely on diagonals) and, like a pawn, could step one ...
- 33.1k
-2
votes
0
answers
99
views
All USA States covered by matchstick digits
Inspired from All Europe Countries Segmented.
You are given the following map of the States of USA:
Using the above map, you must place matchstick digits such that all 50 states have exactly one ...
- 7,888
6
votes
1
answer
208
views
How many two-coloured tilings of the plane are there using F-pentominos?
I looked at finding two-coloured F-pentomino tilings of the plane today. I have a program that tiles rectangles and also handles wrapping of each axis, ie tiling a torus. Tiling a 10x10 torus I get ...
- 4,420
13
votes
3
answers
1k
views
All Europe Countries Segmented
This puzzle is an attempt of improvement to my previous closed and poorly described puzzle.
You are given the following map of Europe:
And the following list of 50 Europe countries:
Albania
Andorra
...
- 7,888
1
vote
1
answer
405
views
All countries segmented [closed]
You are given a 2 dimensional world map of all the countries (it can not be on a sphere), dated in the 21st century (no dinosaur map allowed!), large enough so that a human can distinguish France and ...
- 7,888
6
votes
1
answer
718
views
Creating the hardest 6x6 maze w/ 9 walls
We had a previously great puzzle called "Creating the hardest 6x6 puzzle".
My question is: What is the longest forced tour if we are limited to using exactly 9 walls?
The Puzzle Basic Rules:
...
- 33.1k
8
votes
1
answer
365
views
Coins in Pockets 3 - Cough Up!
A follow-up to Coins in Pockets 2. Differences to that puzzle in bold.
The strategy will probably be based on the solution to that previous puzzle - you might want to try it out first (or just focus ...
- 2,069
6
votes
2
answers
727
views
Coins in Pockets 1.1
Consider the following very good puzzle setup by Nis J?rgensen:
N people are sitting around a campfire. Between them they hold C coins, with C < N/2. You are given the pattern of "same" ...
- 33.1k