As of May 31, 2023, we have updated our Code of Conduct.

# Questions tagged [strategy]

A puzzle whose solution is a methodological plan of action for realizing a specific goal.

706 questions
Filter by
Sorted by
Tagged with
1 vote
151 views

### Minimum moves to lose grid game

Here is a number grid: And here is the rule for how to move: A move consists of selecting two adjacent squares (either vertically, horizontally or diagonally) and dividing the sum of the two numbers ...
• 12.9k
321 views

### Minimum number of moves to win this number game

This puzzle is inspired by this puzzle that I answered: Is equality possible? Here is the number grid from that puzzle: And here is the rule for how to move: A move consists of selecting two ...
• 12.9k
751 views

### 1000 gold coins to share with the knight

Note: This riddle is similar to this riddle: 1000 gold coins to share with the king, except now YOU are the king, and the rules are switched up a bit. And the situation is wackier... You are the King ...
• 12.9k
197 views

### Spies in Puzzlevania

What I am about to tell you doesn't leave this room. For the past year, we've grown concerned by occurrences in the nation of Puzzlevania. We believe a major attack may be imminent. However, the ...
• 636
3k views

### 1000 gold coins to share with the king

You are the knight of a great kingdom in an unknown world. Your king sent you to a dungeon and you killed the dragon and got 1000 gold coins from the dragon’s lair. Normally, you are supposed to give ...
• 29.9k
98 views

### How to know which head belongs to which tail in a bunch of wires? [duplicate]

I saw a puzzle in a contest in Iran held by an association called "Rahneshan" and the original text of the contest is uploaded HERE and of course both website and text are in Persian. ...
189 views

### A harder robot-control puzzle

The goal is to find a sequence (a "program") of max 5 commands that will move the triangle (the "robot") through the grid and make it visit all the squares marked with a star. Two ...
• 685
1 vote
130 views

### Minimise battle time in Monster's Den

So there is this excellent flash game, Monster's Den. In order to make a high score, I must complete many battles..this question is about battles with the Legendary Monsters. The target is to reduce ...
• 4,344
1k views

### A nice robot-control puzzle

The goal is to find a sequence (a "program") of max 6 commands that will move the triangle (the "robot") through the grid and make it visit all the squares marked with a star. Two ...
• 685
615 views

### Lap Theory Optimal Betting Game

Three prisoners are seated at a table. Each of them has a mobile phone on their lap, and they are not allowed to look at anyone else’s phone (and obviously no other form of communication is allowed). ...
• 6,651
279 views

### 19 balls and a scale [duplicate]

You are given 19 identical-looking balls and a two-sided scale. One of the balls is different, either lighter or heavier than the others. Using 4 weighings of the scale, how can you determine which ...
• 29
502 views

### Three way duel, which guns to choose?

Alice, Bob and Carole are involved in a game of three way duel. They take turns to shoot in the order of Alice-Bob-Carole-Alice-... until only one surviver is left standing. The rule is very simple: ...
• 5,599
732 views

### One truthteller, one liar, and two randoms - least questions to identify?

I have landed on a new planet and there are 4 people there. One of them is a truth teller and they always speak the truth. The other is a liar and they always lie. The other 2 are random and they ...
• 2,129
1k views

### Two player Monty Hall variation

Alice and Bob are going on a game show as partners. In this game, there are three doors, which contain a car, the car keys, and a goat, which are arranged randomly and secretly behind the doors. Alice ...
• 3,801
294 views

### A mix of 2048 and Match 3

I was playing a game and thought of this problem: Rules There are 4 distinct tiles on a $6\times6$ grid. The game starts out with one block on the board. You can shift all the tiles in one of the ...
• 5,191
120 views

### Quarter Rolling Die

Quarter rolling a die means triping it on any of the 4 sides adjacent to its base or face in contact with the flat surface. Using the assembled die and quarter chessboard: You can place and align the ...
• 6,616
474 views

### Modifying the puzzle: Cooperative hat-guessing, no mistakes, 3+ colors

Following Guess your hat color, but you don't have to and it's interpretation via Covering codes I tried to create a puzzle with more hat variativity, i.g. 3 types of hats. 4 hats are put on 4 ...
• 16k
1 vote
571 views

### How do you force a win in 4x4x4 TicTacToe

I have read in the wikipedia page of TicTacToe that it is possible for the first player to force a win in a 4x4x4 board. I tried to find a strategy on how to do it online but failed. So, how do you ...
• 736
543 views

When I start to teach probabilities, I challenge my students with the following: Thelma is 16 years old and can only go out at night if one of her parents gives her permission. She knows her father ...
• 2,253
708 views

### 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 ...
• 1,880
880 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, ...
• 1,880
238 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 ...
• 301
459 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 ...
• 1,880
363 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 ...
• 63
4k 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 ...
• 41
550 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 ...
511 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 ...
• 29.3k
1k 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 ...
560 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 $S =$ &...
• 33.9k
706 views

### How many rolls on average to get N dice to all show the same value?

So for example: if $N = 3$ I roll and get -> $1,2,3$ I re-roll the $2$ and $3$ -> $1,4,4$ I re-roll the $1$ -> $2,4,4$ I re-roll the $2$ -> $4,4,4$ In this case, it ...
• 281
403 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 ...
• 5,599
303 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 ...
• 117
228 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 ...
420 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 (...
• 6,616
285 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, ...
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, ...
• 2,220
99 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 ...
• 21
387 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, ...
• 1,161
457 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 ...
• 431
2k 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 ...
• 3,276
1 vote
97 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 ...
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-...
• 480
4k 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 ...
• 423
544 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 ...
• 29.3k
1 vote
158 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 ...
• 5,102
3k 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 ...
• 11.8k
220 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 ...
• 11.8k
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 ...
430 views

### Two of 18 coins are counterfeit

There are $n=18$ coins, and we know exactly $2$ of them are counterfeit. All counterfeit coins differ from normal coins in weight, but otherwise their weight is not known. They can be heavier or ...
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 ...
• 5,102