Questions tagged [strategy]
A puzzle whose solution is a methodological plan of action for realizing a specific goal.
12
votes
3answers
2k views
99 coins into the sacks
You have 99 coins that you need to place into any number of sacks. After doing so, you write on each one the number of sacks that are lighter than that sack. For example, if you put 98 coins into one ...
5
votes
7answers
592 views
The selling of the sheep [closed]
I do not know the answer to this puzzle, and I found it in some old files I had
Many years ago, there was a shepherd with 3 children. One day, while talking to the owner of the herd, the shepherd ...
6
votes
1answer
211 views
Dividing the gold
There is a king and 3 women in a castle. One day, the king give 3 women a total of 100 golds. He said that each woman can propose an idea to share the gold among themselves. If the proposal passed ...
4
votes
2answers
210 views
100 prisoners' names in boxes, against smart warden
My question, which I do not know the answer to, concerns the classic 100 prisoners and 100 boxes puzzle, summarized below. The solution to this assumes the names are placed in boxes randomly, and gets ...
26
votes
8answers
2k views
Wolves and sheep
All the sheep were living peacefully in the Land of Shewo. But suddenly they were struck by a danger. A few wolves dressed up as sheep entered the territory of Shewo and started killing the sheep one ...
17
votes
5answers
677 views
Blindfold Bingo
Congratulations, you have been selected from among the audience to compete in the fabulous Blindfold Bingo challenge! (cue annoying, yet catchy theme music.)
Here you see our perfectly ordinary Bingo ...
6
votes
2answers
237 views
“Balls in Boxes in a Sack” Weighing Problem
This puzzle is based on a competitive programming problem in SG NOI 2019.
Let's assume there are $100$ balls with some labels (e.g. with $100$ different marks on them) having different weights of ...
7
votes
3answers
385 views
Writing differences on a blackboard
The numbers 25 and 36 are written on a blackboard. At each turn,
a player writes on the blackboard the (positive) difference between two numbers
already on the blackboard, if this number does not ...
14
votes
1answer
421 views
Keeping a ball lost forever
Suppose you can make a rectangular maze, where each cell (apart from the bottom-right) can contain an arrow in one of the four directions (up, down, left or right) of your choosing, except for those ...
8
votes
2answers
284 views
What other strategies can I use with this sudoku puzzle?
I have a sudoku puzzle that I have been doing for 270 hours.
I never guess numbers and always thought that every move in sudoku had to have a logical explanation. Until the app generated this random ...
3
votes
1answer
181 views
$n$ buttons on a table
A generalization of Four buttons on a table:
In a certain room there is a rotating round table, with 4 symmetrically located indistinguishable buttons. Each button can be either ”on” or ”off”, ...
0
votes
2answers
149 views
Finding a line on a plane
Imagine you are on an (in)finite 2d-plane (and confined to walk on it). There's a straight line somewhere on the plane, but you don't know where it is and neither can you find it by looking from afar. ...
5
votes
2answers
183 views
Pick and roll and guess
The caretakers in a Home for the Golden Agers decided to have a guessing game for the old fellows. Two partner teams shall play the game and the winners shall have free access to the fridge for 1 week....
3
votes
1answer
160 views
Another variation of the game of Nim
Two players set several piles of chips. The piles are arranged in a row from left to right. By turns each player takes one chip from one of the piles and adds at will as many chips as he/she wishes (...
15
votes
2answers
428 views
What is the optimal strategy for this triangular board game?
I saw a board game somewhere and I want to know the optimal strategy for it.
The game is played on a triangular board with 21 slots:
The two players, red and blue, take turns to put numbered circles ...
1
vote
1answer
112 views
Guess the coin toss [duplicate]
You and your friend are put in two different rooms with just a coin and no way to communicate. You both toss the coin at the same time.
Your task is for at least one of you to guess correctly what ...
-1
votes
1answer
92 views
Important steps and strategies for solving puzzles [closed]
What are the necessary steps for solving any puzzle?
10
votes
3answers
630 views
Fight Battle 21
Based off a very, very well-known puzzle
The new RPG, Fight Battle 21, is now here! Now with the same three characters as the previous 20 editions!
Knight: 6 HP, 60% chance to deal 3 damage
Archer: ...
8
votes
3answers
1k views
Card game rigging
You and your friend are playing a game with a deck of cards numbered 1 to N.
You will first put the deck of cards in whatever order you want. Next your friend will choose an option: "A" or "B". ...
3
votes
1answer
123 views
Space saving dish washing
There are some stacks of dishes on the left side of the sink. There aren't any on the right side. A larger dish can never go on top of a smaller dish (this is valid for all stacks on both left and ...
1
vote
0answers
101 views
What are some tips to solve an environmental-based enigmatic puzzle (EBEP's)?
First, some rough definitions:
enigmatic puzzle: a problem where the goal / answer should be well-defined (e.g. enter a certain word or phrase into an form which is accepted; find a clue to a ...
8
votes
4answers
523 views
Maxit negotiations
Your military junta has recently overthrown the government of Malta and taken control of the small island nation. As a way to finance your wise and just dictatorship, you have decided to threaten the ...
31
votes
2answers
660 views
lolcatz can haz ur infinit cheeseboard
This is a problem on an infinite chessboard with pieces called lolcatz. They can move like queens or knightriders, but have a strange disadvantage...
... you've never heard of knightriders? Well, ...
0
votes
3answers
339 views
Rullo solving strategy for 2-4
How to eliminate/nominate candidates without guessing?
For the 3s it's quite easy because of the odd numbers but how to get further?!
For thoose who don't know the game, here's a short introduction:...
2
votes
1answer
183 views
Master and Slave versus Bob: easy version
Continuation of: "Sub-puzzle: Master and Slave versus Bob the Violent but Honest Psychopath"
Continued in: "Master and Slave versus Bob: hard version"
Previously I described a game that is played ...
1
vote
1answer
276 views
Master and Slave versus Bob: hard version
Continuation of: "Sub-puzzle: Master and Slave versus Bob the Violent but Honest Psychopath" and "Master and Slave versus Bob: easy version"
The hard version is identical to the easy version (see ...
1
vote
3answers
312 views
Sub-puzzle: Master and Slave versus Bob the Violent but Honest Psychopath
[I created this as a sub-puzzle to "Strategy to beat the Casino reversed", that has been sitting unsolved for months. You may wish to read that puzzle first, but this is self-contained. My answer to ...
6
votes
1answer
270 views
Another 'Find the Path' Puzzle
Based on user477343's Find the Path puzzle I have produced a slightly larger puzzle based on a similar mechanic. Goal is as follows:
Draw a continuous path between the two red dots.
The path must ...
8
votes
4answers
376 views
A “Find the Path” Puzzle
I invented a puzzle, inspired by Simon Tatham's Portable Puzzle Collection. Is there anything that it could improve on? Was it too easy, or was it too hard? Anything I could add? What must I call it?
...
16
votes
2answers
345 views
If you have 3 random numbers between 1 and 27 can guess the fourth?
Problem:
Ashley and Ivan want to impress their friends and come up with a magic trick:
One of their classmates comes up with 4 unique random numbers between 1 and 27 and tells them to Ivan. Ivan ...
1
vote
1answer
84 views
How to make a 2v2 rotation with 5 people
I'm running a volleyball club at school and we currently have 5 active members. Is there a way of having everybody play in a duo with everybody else and have one person sit out each game practising? I ...
4
votes
1answer
220 views
Are there basic weighing puzzles requiring adaptive strategies?
Let us define a basic weighing puzzle as such:
There are <number> identical balls, except one weighs <more/less/a different amount than the others>
A balance scale may be used to weigh two ...
3
votes
4answers
302 views
Classic 2 Guards But With 3 Doors Instead
So the rules are almost the same :
You get to ask just one question to whichever guard you want to (just 1 guard; asking both guards is not allowed)
There are 2 guards, one tells the truth and ...
0
votes
0answers
120 views
Best strategy for Multiple Blindfolded 3x3 Rubik's Cube event (WCA)
The MBLD event is quite hard on the technique and the memory , testing the 3x3 Blindfolded method.
The cube placement strategy as discussed by few officials stand at : Cube Placement
The other ...
1
vote
2answers
633 views
Strategy in Coloring a 4x4 empty grid and the one who completes any 2x2 area of the grid is the loser
Alice and Bob are playing the following game: They have a 4x4 empty grid and take turns coloring one square each, starting with Alice. Assume that both players will colour the squares in with the same ...
7
votes
6answers
860 views
Single-pile Nim with Three Players
Three perfectly rational logicians (Alice, Bob and a Quetzalcoatlus) are playing a game. (Charlie couldn't make it, so he asked the Quetzalcoatlus to fill in for him.)
The rules are very simple:
...
2
votes
5answers
363 views
A Very Odd Game
Barry, John, and Caleb, all perfect logicians, were very bored one day and they decided to come up with a new game (they haven't got a name for that game yet). The rules were quite simple :
The first ...
2
votes
2answers
253 views
Radioactive River
You, Alice, Bob, Charlie, Daniel, Elisa, Fred, and Greg are playing a cooperative game called Radioactive River. They have to get across a 20 meter carpet/radioactive river, and they only have: 3 ...
11
votes
6answers
701 views
I Have To Be With Them!
It's almost time for another year of school! But before school starts, Principal Little needs to form classes. Because there are so many people in a class, the parents are always complaining, asking ...
12
votes
3answers
344 views
Guffin factory regulated heist
I work at a guffin factory. I manufacture guffins and have an unlimited access to guffin storage. I can fit up to 20 guffins in my bag, get them home from the factory and nobody will chase me.
You ...
1
vote
2answers
280 views
Solution or Origin of logic puzzle
This is not my puzzle and I do not know the solution. This was shared to me by a friend. Their former boss told them this riddle. I was told this question originated from Steven's Institute of ...
2
votes
1answer
650 views
$\verb|Eight Circles|$
An entry in Fortnightly Topic Challenge #37: Rare and Endangered 1
Materials
Pencil;
Eraser;
Blank A4 sheet of paper; and
A ruler (also to use as a straightedge).
Puzzle:
Draw a square with a side-...
7
votes
1answer
220 views
Domino Tiling Game
Two players are presented an $n\times n$ grid. They take turns placing a piece on the board until no more moves are possible. The last player able to make a move is the winner. The pieces are $2\times ...
13
votes
4answers
3k views
A dice game, what is the optimal strategy?
Alice was walking on the street when she came across a man playing with a die. She could not help trying to check if the die was loaded and while she was concluding that it wasn't loaded, the man ...
8
votes
1answer
452 views
Clearing the Robot Museum
The grand opening of the Collapsible Robot Museum is just 1 week away in the robot nation of Robotia. The museum is unique because shortly after the museum closes, the building collapses into a flat ...
0
votes
6answers
446 views
Data Sharing Between 3 Players [closed]
Consider a situation in which two companies hold data about individuals: the first company holds individual's names, and their age.
The second company also holds the individual's name, but instead of ...
30
votes
3answers
978 views
Snakes on a Plane!! 2
An entry in Fortnightly Topic Challenge #35: Restricted Title 1. Inspired by the title of this xkcd comic, but in no way related or affiliated beyond the shared name.
It's a well known fact that any ...
8
votes
4answers
414 views
Ten users, three lights but it's a chatroom
This is a variant of the classic problem of m prisoners n lights. (Example may be found here but note that the requirements are not exactly the same)
The goal for you, however, is different. You want ...
2
votes
0answers
118 views
Ten users, ten deadly collars and three lights [duplicate]
One day, 10 puzzling.SE users, including you, find yourselves in a horrible prison. Each of you has a deadly collar, presently lethal. It is safe to take off only when all of the 10 collars have been ...
8
votes
5answers
399 views
Two person game, choosing an integer between 1 and 30?
Suppose two players are playing a game. The first player chose an integer, n st. $n \in \left\{ 1,\ldots ,30\right\}$. The second player picks a different one. After that, a random integer x st. $x \...
