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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.

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Ode to Regular Expressions

Robert loves regular expressions and ever since his friend Jean introduced him to Regex Golf, he spends most of his time trying to find the shortest and most elegant solution possible. Robert is also ...
3k views

decipher RGXWSTLSQLITL where (ABCDEF=QWERTY)

decipher RGXWSTLSQLITL where (ABCDEF=QWERTY) How do you solve this?
1k views

Lego brick towers

Disclaimer: I'm honestly not sure whether this question is best placed at Puzzling, Maths, or Programming SE, but I'm interested in the best solution, and I'm sure mods will shift the question around, ...
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 ...
632 views

Troubles with a Rogue Circuit

Edit : Made the final step to the solution easier to solve, also added hint. I’m not quite sure what’s happening over here, but I believe you guys might be able to help. I started noticing ...
644 views

The lone builder

You are a lone builder. You have to build a city on a 10x10 initial empty grid. You can place: a street, which is a blue cell on the top of any cell, a tomato shop, which is a red cell on any cell ...
1k views

What is the password to the diamond temple?

You are searching for the diamonds in a remote area. After hours, you see a temple with a diamond engraved. You realise that this is the diamond temple. The temple has the following also engraved: ...
793 views

Files hidden in files (puzzling question)

Not sure if Puzzling is the right place for this, but I couldn't find anywhere else to ask. I've been seeing this image circulating around a few Discord servers: When converted to mp3, you get the ...
505 views

What does this C function do?

C source code at: http://pastebin.com/6Bywk5mf Will also function in Java. Note that in C ...
656 views

Dragons: Myth or MathJax?

Ever use MathJax to display mathematical expressions?   Expressions related to fractals? Ever used it to display fractals themselves?!   The time has come. These fractals are based on the ...
2k views

What movie quote does this represent?

This describes the quote: ...
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: ...
818 views

Little bit of a code in binary :)

Decode it and prove it :) Share if you think someone else can solve it. Here is a little bit of a challenge for lovers of code and encryption, the hints should be evident, but I think that I would ...
559 views

Make some Guacamole!

Subject: Mole Date: Sat, 31 Mar 2018 14:20 From: Chowzen {chowzen@segmented.org} To: PuzzlingEnthusiast {pe@puzzling.se.edu} PE: As you may be aware,I am the leader of an ...
727 views

Figure out the language

I recently watched a documentary where they talked about messages sent into space and how they imagined aliens figuring out how to understand them. They used math and geometry in clever ways. I ...
390 views

Help me decompress this old file

A long time ago in a basement far far away I created my own operating system. Unfortunately I made a foolish mistake when designing the file system. I choose a single byte for representing file sizes. ...
455 views

Conway's Siege of Life

They are immortal and they are killing us. We may not be able to kill them, but we might be able to keep them occupied, distracted, for eternity. But we need to figure out how. Before there are no ...
344 views

Only Losers Read the News Note the enigmatic tag. It's not meant to be clear what you're seeking.
692 views

“I like things done once”

You disable the security shields. Dr P releases his minions. Suddenly you hear the red siren. 'Code-Red' says the computer. You smell smoke. You see the background a blur and noises in the air. ...
2k views

A mosquito is born at T=0 and after 2 seconds makes a new mosquito every second, how many mosquitos at T=8.5? [closed]

One mosquito is born at T=0 and after 2 seconds it makes a new mosquito, and another every second thereafter. All such mosquitoes have this same property and do not die. How many mosquitoes there are ...
1k views

Optimizing month abbreviation to number

(This comes from a real-world requirement.) The idea is easy - if you have the three-letter abbreviated name of a month, say "Jan", get the numeric month number (for "Jan", 1). Sure, sure, pick a ...
738 views

Shades of Gray - Perception vs Reality

Within each individual "view-finder" frame below, all of the pixels are the same shade of gray. Frames A, C, and E appear to be a darker gray while frames B and D appear to be lighter. However, based ...
379 views

First Cryptography Puzzle

When adam and eve sinned, apple was the key. Lies of the Serpent, they both believed. Alternate: 56 108 87 97 119 53 97 43 57 49 68 105 66 51 121 115 84 54 120 51 81 65 61 61 I'm looking for just ...
625 views

MathJax exposed

WARNING   \$ \color{red}{\boxed{\boxed{ \sf ~~{ \large N \, S \, F \, P \rlap{\small P\&CG~SE} }~~~ \huge\raise-.2ex\...
209 views

Octospider Cousins

This was inspired by the octospiders in the Rama series by Arthur C. Clarke. Reading the series is not a requirement for solving the puzzle and actually wouldn't help at all besides being able to say, ...
316 views

The Serpent Stronghold

You come to the door of the stronghold. You recall what the scriptures say: You must speak the right words, and the door will open. But what words? It doesn't say. You have a look at the door in front ...
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? ...
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 < ...
231 views

One, two, and three weeks from now

I just came across this note in my office! Date of writing: Sept. 9th, 2015 In exactly one week from today, and then a week from that date and then another week afterwards, something will ...
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. ...
318 views

A curious circuit

During our latest space mission to Mars, humankind has retrieved a curious alien circuit. Our historians think it must be a calendar of some sort. After speaking with some alien linguists, we know ...
300 views

Generating different difficulties in custom puzzle

first of all this is my first time asking something here so please let me know if I am doing something wrong or asking it on the wrong place. I have a custom puzzle model where I need to generate ...
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 ...
3k views

Creating a Kakuro puzzle with unique solution

I start with a grid of black and white cells. I randomly populate the white cells from numbers (1-9) using kakuro rules. Then I calculate the horizontal and vertical sums. I remove the numbers from ...
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 (...
962 views

Easter egg puzzle

A friend of mine sent me a puzzle which has eggs labeled with numbers 76 95 228 361 158 171. The puzzle is asking, which egg doesn't belong in the nest. All of the eggs have different colors too which ...
577 views

John's first pixel drawing

Story continuation based from this first riddle and this other riddle. Bob was enjoying his day off at home when he received a message from John. John sent him a picture of a piece of art, the first ...
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 ...
780 views

How to test for logic operator precedence

While coding in Python, I realized I couldn't remember which is evaluated first: and (the logical conjunctive operator), or (...
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 ...
4k views

Unseen, but Hidden in Plain Sight

This riddle has a single, one word answer, with an explanation as to how you found it. You may be able to make a good, or even correct, guess from just the contents of the poem below, but if you've ...
963 views

What does this program try to tell?

I tried to open an non existent page on stackoverflow and received "Page Not Found" warning however didn't understand what the code next means. Do you know what SO try to tell?
1k views

Find the Rebus in the Rebus

Find the def That(n): def Question(n): return n+1|-n-2 a = Question(n) return a >>> That(42) -1 Clarifications Three hints would be ...
499 views

What song are these lyrics from?

function me(something){ something++; } something != same; Can you guess the song based on the lyrics above?
1k views

The Magician's Card Game

A magician by the name of Jason carries a deck of cards with him everywhere he goes. He has a game where you can say any phrase and a specific card will correspond with that phrase. The goal of the ...
733 views

Scrambled Pizza Order

It's your job to gather the pizza orders for everyone in the lab you work at in New Mexico, but it appears that the order for Richard has become corrupted and scrambled. He attempted to send it over ...
383 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 ...
227 views

Tiling rectangles with T pentomino plus rectangles

Inspired by Polyomino Z pentomino and rectangle packing into rectangle Also in this series: Tiling rectangles with F pentomino plus rectangles Tiling rectangles with N pentomino plus rectangles ...