Questions tagged [strategy]
A puzzle whose solution is a methodological plan of action for realizing a specific goal.
531
questions
15
votes
2answers
512 views
+200
Topological Nim
You and your friend's new favorite game is "topological nim": You take your favorite compact metric space $X$ and a radius $r$. Each player removes an open disk of radius $r$ from the space ...
13
votes
2answers
752 views
A tournament, and a tight personal schedule
A 64-player binary tournament bracket is about to start. You plan to free up your schedule in advance to watch some of the matchups (meaning, you can plan to watch the second semifinal, for example, ...
1
vote
1answer
161 views
How can they attack?
There are four soldier squads planning to attack a town from the north, south, east, and west at the same time.
They are in their positions; now they just need to know when to attack. One of the ...
6
votes
2answers
332 views
A game of 101 stones—win at (not quite) all costs
In the land of Humilia, a tournament game is played between two players with 101 stones in a pot between them. On each turn, a player may take up to five stones from the pot (and must take at least ...
6
votes
1answer
216 views
Crosswords: Maximum number of words in an n×n grid
What is the maximum number of "words spaces" that can be in an n×n crossword, based on the placement of the shaded squares.
Some limitations
No word can be less than 3 spaces in length
...
3
votes
1answer
178 views
What is this puzzle and what is this solving strategy? [duplicate]
This puzzle is a mini game in an app I recently downloaded. In the game it is referred to as a Mobius Puzzle(after some searching I found referenced as a TwoBik Puzzle). But I cant find any other ...
7
votes
2answers
433 views
Balance the nails
Someone I know handed me this puzzle, I have seen a couple of solutions for it that follow the instructions and don’t involve bending the nails, etc.
Can you figure out how to balance the 6 nails on ...
9
votes
2answers
219 views
Bicoloured 2048
I made a new puzzle game that you can play here. It is a variant of 2048 where there are tiles of two colours. You need to merge tiles of the same colour and value to increase your score. In more ...
7
votes
3answers
336 views
The 15 Pebbles Game
This is a game for 2 players - Each player uses a different coloured marker or pencil, there are 15 pebbles in total.
Players take turns to colour 1, 2 or 3 pebbles (player chooses how many). When all ...
3
votes
2answers
404 views
A Puzzle about “Codeforces Subsequences”
I'm quite intrigued by an "easy" problem in recent Codeforces contest: Codeforces Subsequences.
In this problem, you have to create a string $T$ as shortest as possible such that $S = $ &...
10
votes
3answers
248 views
Find a good strategy to survive the multiplayer duel
Alice is involved in a duel with $N$ other opponents. She can choose a gun for herself with any hit probability as she wishes. She also prepares guns for her opponents, whose hit probabilities she can ...
-2
votes
2answers
243 views
Battleship puzzle with no clues
Suppose I have a standard Battleship Puzzle, but with no clues (no square uncovered) at the start. Then I'm given 5 "fires" that uncover a square, what would be the best strategy to chose a square to ...
2
votes
1answer
182 views
Based on 9-trains puzzle
Based on this problem, we have got some algorithms that can sort the 9 train cars in a given specific arrangement. But say if the 9 train cars are given in any-arrangement?
Say
ABC
ABC
ABC
...
5
votes
3answers
349 views
Playing the Square Chess
On an ordinary chess board (8x8) without any pieces on it as a starting position, two players will alternately place a pawn on any square (unoccupied) so that the first player that form a square (...
5
votes
2answers
205 views
Simple game of dice - what is the optimal strategy?
The game is pretty simple, whoever reaches 50 first wins, but there are a few important details:
2 players, one die. Players take turns.
Rolled values are simply added up
If you roll a 6, however, ...
49
votes
5answers
6k views
There are 2,001 doors leading to 2,001 hallways. How quickly can you find the way out?
Once again, you have angered the Emperor, and she has imprisoned you in a special prison.
“I do have a bit of good news for you,” the Emperor has told you. “You're only two doors away from freedom, ...
2
votes
1answer
64 views
Is there a strategy for the “2 paths, 1 liar 1 truthful” riddle given an N number of paths, rather than just 2?
I hope this question falls into the correct category. I'm sure the 2 paths , 1 liar and 1 truthful is common, however, is there a general strategy given:
There are N-number of doors/paths/or ...
0
votes
0answers
85 views
Haircut in an imaginary town [duplicate]
An imaginary town has 2 barbers
one of them has a great haircut
the other one has a bad haircut
whom should you get a haircut from ?
8
votes
1answer
176 views
A rubik's cube that fights back
After the incidents of Skyfall, 007 remembered a quote Q had said when he was accessing Silva's Omega site :
It's like solving a Rubiks cube that's fighting back.
007, intrigued by this statement, ...
9
votes
5answers
306 views
Find the optimal strategy for this dice game
You are playing a game: You have $6$ standard 6-sided dice that are all rolled at the start of the game. The sum of dice values is your score. Each turn, you can take any (or none) dice and reroll ...
6
votes
7answers
1k views
Five minutes puzzle: Multiway switches
Here's an easy puzzle that should take you only five minutes to solve, inspired by my hallway. Most intuitive answer get the mark:
Six switches control the same light bulb in a multiway switching ...
1
vote
0answers
80 views
TestGameExamination [duplicate]
You are given 10 sets of papers with 10 questions each. Answer to each question is from 1 to 4. You somehow get your hands on the answer sheets and able to memorize each answer (Answer sheets only ...
-1
votes
1answer
6k views
Can you guess the lock's passcode? [duplicate]
A lock's passcode is composed of three digits. Five incorrect passcodes are given below, each with a hint to the correct passcode.
2-0-6:
Two of the digits are correct but are in the wrong places.
6-...
17
votes
3answers
3k views
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 ...
6
votes
1answer
490 views
Playing blindfolded 2048
Suppose you are playing many 2048 games, all blindfolded. As usual you can press left, right, down, or up to move the tiles. When there are no more moves the game terminates and you are told your ...
1
vote
3answers
133 views
playing “Coins on a table” against a distracted friend [duplicate]
This puzzle is a follow-up of Coins on a table (warning: the link contains the answer to the original question).
You are playing a game against your friend Alice:
first Alice places one coin on a ...
18
votes
2answers
2k views
Playing with one Queen on a chessboard
Alice and Bob play a special chess game with alternate moves. Alics starts with an empty chessboard and puts a Queen at a field in the first row (A8-H8) or the right column (H1-H8). Now Bob is moving ...
2
votes
1answer
137 views
Four unfair dice
On a table there are four standard six-sided dice with faces numbered 1, 2, 3, 4, 5, 6 each.
Alice starts and chooses a die. Then Bob chooses a die and both throw the dice.
The winner is the person ...
13
votes
8answers
3k views
How could Larry get his friends on a plane without knowing their weights? [duplicate]
This riddle was inspired when I watched the latest (as of this post) episode of Curb Your Enthusiasm (S10E4), in which Larry is faced with a dilemma that he never really solved. The dilemma is as ...
12
votes
3answers
1k views
The Troll, the dwarves and the gloves
A group of $N$ dwarves are caught by an evil Troll. As usual the Troll gives the dwarves a chance to escape if they solve a puzzle he created just for the occasion.
Tomorrow morning each dwarf will ...
20
votes
1answer
841 views
Unbalanced weight of boxes
You are given a traditional balance scale with two pans (no reading) and 6 boxes with the following properties:
1) the weight of each box is a positive integer number
2) if you put any number of boxes ...
10
votes
1answer
397 views
Is Oh Tetris Oh! always a draw?
Alice and Bob were playing Oh-Tetris-Oh!, when they decided that every game must be a draw (played intelligently).
Can you prove this?
(Oh yes, the rules: A $10\times10$ grid, you can pick any ...
10
votes
3answers
364 views
Wizard's Labyrinth
A thief has snuck his way into the wizard's castle. After traversing a plethora of magical traps and illusory walls, he finally spies the wizard's hidden stash of gems beyond the end of a long ...
1
vote
3answers
1k views
The missing number
The integer numbers from 1-30 are mutually communicated to you one by one in a random order (one number about every 5 seconds).
However exactly one of those numbers is not communicated.
What is a ...
10
votes
0answers
294 views
Quantum tic tac toe strategy
Most of us learn tic tac toe early in our life. Also, it is easy to find an optimal strategy for playing.
How about Quantum tic tac toe? What is the optimal strategy for playing it?
Rules
On a ...
3
votes
2answers
126 views
How to effectively hide an earth rebooter thingy [The Good Place Season 4 spoilers]
This puzzle is unsolved. I don't know if there is a solution or how to solve it. I'm also not sure what type of puzzle this would be, so if anyone wants to correct the tags, feel free.
Imagine you ...
0
votes
0answers
236 views
A Logician's Game of UNO Flip
Two players are in the middle of an ongoing one-on-one game of UNO Flip, with all its standard rules in effect.
Play is currently Light Side Up. It is Player B's turn. Player A has 3 cards remaining, ...
11
votes
5answers
452 views
Crossing the desert
There are explorers that want to go as far in the desert as possible. One explorer can carry water for himself for 10 days. If they would all stick together, they would have enough water to go 5 days ...
10
votes
9answers
2k views
Find two coins using a balance scale
You are given 20 identical coins. 18 of those coins have a weight of 10g each, 1 coin has 9g and 1 coin has 11g.
You are given a traditional balance scale with two pans (no reading).
What is the ...
14
votes
1answer
378 views
A flower-shaped robot-control puzzle
The goal of this puzzle is to find a sequence of max 5 commands that will move the triangle through the maze and visit all colored squares.
Three types of commands can be used:
F0 makes the sequence ...
31
votes
1answer
3k views
How to get a bowl with one liter of water
You are given a rectangular bowl with size 5 x 30 x 40 cm and you should put exactly one liter of water into the bowl. You go to your kitchen, where you can put the water directly into the bowl from ...
0
votes
1answer
137 views
Find the lowest floor from which Venus eggs break [duplicate]
Venus gave you two eggs because she wants to test their strength.
She lives in a 100 floor building and she wants to find the first floor above which the eggs break when thrown out of the window.
...
8
votes
1answer
256 views
Maximizing Product of Selected Cards
Jennifer is playing a game. The Ace through King of spades are taken from a standard playing deck and laid out facedown on the table. At any time, Jennifer can select two cards and reveal them, and ...
7
votes
2answers
293 views
A Bored Jailer and His Number Game
A bored jailer tells a prisoner that if he can guess a secret number he will be set free. The rules are given that the number will not be more than three digits in length and the prisoner may guess ...
15
votes
2answers
616 views
United States Towns/States Traversing by Name Puzzle
I’m new to puzzle solving in a structured way, so please go easy on me, but I thought the following was interesting (sorry if it’s not or seems like grunt work). I came up with this while staring ...
-6
votes
1answer
122 views
Another how to kill 7 submarines
7 submarines are placed on an x, y grid - 0 to 111. They are located on whole numbered locations. Each submarine starts from any selected location with a given fixed speed and fixed direction, ...
6
votes
1answer
314 views
Russian Roulette (Redux!)
You are challenged to a game of Russian roulette with a six-chamber revolver, but you and your opponent are allowed to change the outcome of the game in different ways. Here's how the game will ...
2
votes
1answer
176 views
How to kill 7 submarines
7 submarines are placed on an x, y grid - from negative infinity to positive infinity. They are located on whole numbered locations. Each submarine starts from a location with a given fixed speed and ...
8
votes
3answers
1k views
30 fake coins out of 99 coins v2
Follow up question to my other question, but totally different methodology required.
You are given 99 coins which consists of 30 fake ones. You also have a digital balance scale with perfect ...
12
votes
3answers
2k views
Can you catch the thief?
This was a puzzle I recalled from university a couple of years back. I don't know what the original puzzle is but if someone knows it, please let me know so I can credit the source.
You are a police ...
