Questions tagged [computer-puzzle]
A tag for puzzles dependent upon some degree of computer literacy - for instance, requiring basic familiarity with operating system usage, encryption or programming.
317
questions
8
votes
2answers
805 views
Can multiple wall timers turn lights on or off when required?
Imagine we have some simple mechanical 24 hour wall timers like this:
There’s one restriction though, they’re badly designed so each one can only turn on once and turn off once in a 24 hour period (...
18
votes
3answers
5k views
A shy person in a queue
I'm so shy when between people.
When in a queue, I'd like to be the last.
That's the only time when I'm not shy.
When consuming food, I'd take one or two, or even four, depending on the context.
What ...
2
votes
1answer
176 views
Molly and a pseudocode
Molly was given a pseudocode by her teacher and told her you need to understand the pseudocode to answer the riddle.
Riddle:
I am _________ like universe and stars
You will find me in computer ...
5
votes
1answer
261 views
map 5 unequal ranges to id
This is actually coming from a business place, but it's all about being able to do math tricks, and that's why I'm posting here.
I want to implement the following function:
...
9
votes
1answer
354 views
“Brainf*ck, but not really.”
Yesterday, I organized a contest with various challenges the participants had to solve. I put 6 very simple puzzles that were solved almost instantly, and the deadline was supposed to be until Sunday. ...
0
votes
2answers
164 views
Hunting for treasure in 1-d grid [duplicate]
In a castle, there are N rooms in a line. Each room has a door to the
two neighbouring rooms (or the one neighbouring room, for the rooms at
either end). A treasure is hidden in one of the rooms. ...
8
votes
1answer
280 views
What is a Fade Word™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles.
If a word conforms to a special rule, I call it a Fade Word™.
Use the ...
6
votes
5answers
456 views
What is my name? It's not “traveler”
The answer to this puzzle is my first name. What is it?
If no progress is made after a week or so, I'll slowly give hints. It's not too hard of a puzzle, so long as you take everything into account.
...
2
votes
2answers
177 views
How to find number of times sequence element $1$ is approached and from where?
Consider a sequence $1,-1,-1,-1,-1,-1,...,-1$. Start at the first element and move down the sequence according to the following rules:
1) If you jump from a $-1$ to another $-1$, turn the latter into ...
10
votes
2answers
1k views
sorting 4 numbers using Min - Max boxes
Min-Max is a box that is capable of determining which of the two numbers is the higher (Max) and which is lower (Min).
I need to use minimum amount of boxes in order to sort 4 different numbers (any ...
0
votes
1answer
165 views
Find the 33rd two characters, and where they belong
I'm working on a puzzle. I'm about 75% of the way through solving the puzzle.
The only thing left is you hash 33 two character pairs. I have 32 two character pairs.
Possible characters are [a-z, ...
8
votes
6answers
837 views
Restoring order in a deck of playing cards (II)
Michelle has a deck of 52 playing cards in a pile with their backs facing up. She takes the first 2 cards in the pile, turns them over, and places them at the bottom of the pile. She now takes the ...
13
votes
3answers
2k views
Restoring order in a deck of playing cards (I)
Michelle has a deck of 52 playing cards, stacked in a pile with their backs facing up. She takes the first 2 cards in the pile, turns them over, and places them at the bottom of the pile. She now ...
2
votes
1answer
147 views
The “Jumbled” Cipher
The elusive "Jumbled" cipher has stumped scientists and cryptographers alike...
Not really, but it will stump you soon...
The Jumbled Cipher is a mysterious text cipher that puts text into an ...
19
votes
2answers
507 views
The Sequencer - da-da-daaa!
This is what the diagram on the machine looked like:
And this is the output that was in the box.
...
3
votes
2answers
149 views
The fantastic matrix
Here's another question that I have been asked in an interview lately.
Let $M$ be an $n × n$ matrix whose values are $”+”$ and $”-”$. M is called fantastic if it is possible to make all it's values $”...
17
votes
2answers
514 views
Maximum Height of a Hotel with Strange Elevators
I encountered this puzzle many years ago, and I think back on it often as it is unique and thought provoking. As far as I know nobody has proved the given solution as optimum, so it may still be ...
20
votes
4answers
811 views
Consecutive integers around a circle
Find a block of positive consecutive integers that can be placed around a circle in some order so that any two adjacent numbers always have a common divisor greater than 1.
2
votes
1answer
103 views
Pairwise coprime numbers in a 3 x 3 board
Find all the ways of placing all the digits 1 to 9 in the cells of a 3 x 3 board in such a manner that the seven three-digit numbers that can be read horizontally (from left to right), vertically (top ...
2
votes
0answers
148 views
A partition of 79633 into thirteen parts [duplicate]
The sum of thirteen positive integers is 79633. If placed appropriately on the vertices of this graph, two of them will be joined by an edge if and only if they have a common divisor greater than 1 (...
9
votes
1answer
255 views
Scoring Oracle: Bob easily wins, but how much?
Bob meets a magician with two bags and a chest on a bridge. The magician challenges him with the following enigma:
Here is a bag A, holding 5080 pebbles.
Here is another bag B.
Most of the pebbles ...
7
votes
3answers
224 views
A 4 x 4 Magic Square with Pairwise Relatively Prime Entries
Find a 4 x 4 magic square of positive integers such that any two of its entries are pairwise different and relatively prime, i.e., have no common divisor greater than 1.
What is the least that the ...
8
votes
2answers
232 views
From one color to another
white turns to blue
blue turns to red
red turns to aquamarine
but green stays the same
People from StackOverflow might appreciate this one.
13
votes
5answers
611 views
Labelling a Snow Flake Graph to Attain Minimum Sum
Label the vertices (or nodes) of this graph with positive integers so that any two nodes are joined by a edge (or line) if and only if the corresponding integers have a common divisor greater than 1 (...
16
votes
6answers
550 views
A regular riddle
I'm kept inside a boxy cage.A prefix for the modern age, I make the
messages you create fly at a supersonic rate.
Now that box has me and my friends inside a box with rounded ends. You
can ...
1
vote
2answers
136 views
A Fun, Fantastic, Phonic Cipher!
An old friend of mine recently sent me an email. Being a linguist, he always finds creative (read: annoying) ways to use his words to baffle me. After about five minutes, I usually just give up. ...
0
votes
1answer
172 views
One-word riddle (possibly python)
The question/riddle is: "Never has a snake given such words of wisdom."
The hint is: "Thou shall never pass errors silently!"
It is possible to be related to Python, errors or something like that. ...
8
votes
3answers
1k views
What date encoding could this be?
40 years ago I read a book, but couldn't remember the title. I've been looking for it for a while, and I finally (finally!) found it!
And then I worked out why it took so long. It hasn't been ...
7
votes
1answer
211 views
Can you give us a statement?
Picture an 11x11 grid. Each cell must contain one character. This can be any ASCII character. The contents of the entire row must validate against both corresponding H regex clues. And the contents of ...
10
votes
3answers
586 views
Where is the money?
When I was just a little kid my parents died in a terrible accident, and I was left alone in the world. When I reached the age of 18, I received an envelope with a letter that read the following:
...
7
votes
1answer
126 views
Statements in Java
Each code block translates to a specific statement in English. There is a theme behind the statements. As code puzzles tend to be "easier" (relative to other PSE puzzles) than expected, it will not be ...
4
votes
1answer
101 views
question of royal proportions
I dont know if this is going to be any good but this is my first attempt at on of these puzzles.
The following piece of code relates to a famous saying/phrase/article/piece.
...
3
votes
1answer
253 views
Applied logic challenge problem #2
This is similar to my previous Applied Logic Challenge Problem but with a significant difference at the end which could make this problem somewhat more difficult. Again it is a problem of my own ...
4
votes
2answers
210 views
Applied logic challenge problem
You must determine what can be concluded from the 60 true statements below. The numbers in each statement represent binary values (true / ...
18
votes
2answers
444 views
An Artwork Made from Several Countries
Last year I went to 12 different countries around the world. I made an AI to convert every country that I've visited into a beautiful artwork as a reminder. I input the 12 countries name, then somehow ...
-1
votes
2answers
369 views
What's the Difference?
*not sure if this counts as a real puzzle, but I will ask it anyways.
Can you catch the difference between the 2 following letters?
х
...
9
votes
1answer
288 views
Puzzles like Sokoban?
I am looking for some puzzles like Sokoban or 15-puzzle but more difficult to solve and satisfy the following requirements:
The number of possible moves at each step should be limited, let's say < ...
-3
votes
1answer
83 views
You see me right now… but you can't
Look over here! Oh... that's right. I'm too small to be seen. But you are still looking at me. Crazy! I know right? Here, how about this? You guess what I am! Okay.
Well if I get too much ...
19
votes
3answers
481 views
Ornithogenic Turnover
Peptiberg: Hello, friend. Why do you look so pleased?
Tippgeber: My friend just had a change of profession - from a divisive one to a constructive one.
Peptiberg: Was it a smooth transition?
...
32
votes
3answers
2k views
Mysterious Flash Drive
First puzzle I ever do! Hopefully it won't be too easy or too challenging.
My co-worker just gave me a USB flash drive, which was supposed to contain a couple files of code for me to review. ...
8
votes
2answers
382 views
The “foo” encoding
This puzzle has been solved. Please skip to the bottom of this question for the answer.
Introducing the mysterious foo encoding... based on the common computer programming template variables ...
4
votes
1answer
193 views
What does one do to decrypt this?
'Encrypted': 10101110001011101000000001110111000101011100011101110000000011101110100010111000111010111011100
Context: This is simpler than you think. So simple the solution to this problem would be ...
8
votes
1answer
212 views
Once again, another Linux movie quote!
Because I can't get off this linux movie quote train, here is another one! Can you find the famous movie quote hidden in this linux block?
...
12
votes
2answers
1k views
Yet another movie line on the Linux terminal
What famous quote does the following terminal session refer to?
$ ps -o ppid= -p $u
28342
$ echo $$
28342
11
votes
3answers
5k views
My co-workers left me a message
While refactoring a massive chunk of old code, I found a rather curious section of code commented out that wasn't there the day before. Can you tell me what it means?
...
9
votes
1answer
505 views
Yet another movie quote hidden in Linux
Inspired by this question and this question, can you guess the famous movie quote hidden in this Linux block?
...
13
votes
1answer
1k views
Another Linux movie command
Inspired by this question, here's another Linux command representing a famous line:
cp -a ~she ~
Which line is it?
35
votes
1answer
4k views
2
votes
3answers
388 views
Coding puzzles with pen and paper
At work we are doing a coding competition on hackerrank – it is real coding – you are given input and you have to code a program that produces the correct output.
Now, I would like to promote this ...
2
votes
1answer
136 views
Where is my brother?
Couple days ago, my brother went missing.
It seems like he's ran away from home.
I decided to search his computer, to see if there are any clues to where he might have gone.
All I've found was this ...
