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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.

176
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10answers
18k views

Game of Life: Kill the Sun

Below is an initial state for Conway's Game of Life with a single pulsar. Living cells are white. The area marked with red is your base. You are free to modify any of the red cells, but only those, ...
175
votes
1answer
24k views

Lock your computer when you walk away!

Well this is strange. I forgot to lock my monitor when I walked away from my desk, at work, and one of my co-workers decided to have a little fun. When I got back, I found this little C# console ...
90
votes
6answers
9k views

Fwd: Re: Karen is missing!

From: Ada Hughes <ahughes@fib.gov> Sent: Thursday, April 7, 2016 7:03 PM To: Joe Dorsen <jdorsen@fib.gov> CC: Jason Bernz <jbernz@fib.gov>; IT Guys <cis@fib.gov> Subject: Re: ...
70
votes
2answers
8k views

What famous line does this Linux command line represent?

The following shows a Linux command line with a # prompt: ...
65
votes
6answers
5k views

Bar-coded Message (Reverse Engineering)

This weekend, while totally minding my own business and in no way being suspicious, I just happened to come across the following interesting document: Left page: download as TIFF (100,203,616 bytes) /...
57
votes
5answers
7k views

Game of Life: Move the Sun

Based on Game of Life: Kill the Sun Conditions are the same: Below is an initial state for Conway's Game of Life with a single pulsar. Living cells are white. The area marked with red is your base. ...
54
votes
12answers
15k views

XOR - Is it possible to get a, b, c from a⊕b, b⊕c, a⊕c?

Just got a simple question from a friend; still thinking. Let's share it! Is it possible to get a, b, c when you have a⊕b, b⊕c, a⊕c ? where ⊕ is the boolean ...
53
votes
1answer
4k views

What famous dialogue does this Java code represent?

The following is a text rebus in the form of Java code: ...
51
votes
3answers
3k views

Regular Expressions

...
49
votes
8answers
7k views

James Bond : No Access

James Bond, while working on a top-secret case for many weeks in deep enemy territory, finally collected and stored lots of critical files on his tight-security Linux system. Even though the system ...
49
votes
2answers
4k views

A Robot's Last Words

There, spread out all over the floor, were the mechanical pieces of a robot. Something had torn it apart, and the debris spanned a radius of a few meters. There was no sign of what might have caused ...
41
votes
3answers
1k views

The telltale code

The other night, while writing this Java class that could be serialized into a socket, I fell asleep and had a weird dream. In my dream, when I ran the program, the socket and the class object ...
39
votes
4answers
9k views

Who stole the bitcoins?

Introduction You want to give bitcoins to a person you have met. Part of the deal is to give the bitcoins in the most untraceable way. So you have decided to send an email to him with the address (...
36
votes
1answer
4k views

Chuck Norris vs. This Question

public var c: = Infinity; public var w:Array = [,<...
33
votes
25answers
8k views

I shouldn't have asked him

My roommate (rm) always looks busy in front of his laptop, so I try to start talking to him Me : "Hey, You always look busy, so how do you entertain yourself? Do you have a favorite book, movie, ...
32
votes
14answers
6k views

Debugging with printf()

Bob, a C programmer and a believer of printf-debugging, gets hired by a failing software company. The company is not doing well because they adopt an archaic source code management system which does ...
32
votes
4answers
3k views

Multilayer Image Steganography

Alice, Bob, Carol, and Dan are playing a card game. After they all show their cards, Bob notes that by exchanging two cards the order of the players would be reversed; that is, the player with the ...
31
votes
2answers
2k views

The Time Machine works but my friend is gone!

So my friend Fred and I have been developing a time machine. I know it sounds impossible but we think we've hit a breakthrough! Fred has had a successful test run but he didn't tell me where he was ...
31
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. ...
30
votes
4answers
2k views

They've Noticed Your Puzzling Prowess

They came to your home in the early hours and whisked you away. The four by four's windows were completely blacked out but the agents seemed amicable enough, albeit fairly taciturn. After a while you ...
29
votes
6answers
3k views

Five Linux command line rebus puzzles

Solve the following 5 text rebuses, which are in the form of Linux (bash) command lines. Rebus #1 (solved by Prem) # type beep sound > file.txt 2> file2.txt ...
28
votes
2answers
2k views

Little bits of food

You will come across a question. Answer it.
28
votes
5answers
1k views

The old tinkerer's safe

A client of mine died last Sunday - just as he was born on a Sunday. He was already at rather ripe age, and I had the pleasure to present his last will to his loving and caring family. As far as I ...
27
votes
5answers
2k views

What does this Java main() method represent?

The main() method in the following Java program is a text rebus. What does it represent? ...
27
votes
3answers
8k views

What secret is this massive technical puzzle hiding? [riddles and data puzzles]

There's a game development company which released a mysterious "countdown to reveal" web page, and the page is designed pretty fancy, so everyone in that gaming community is curious about this. This ...
26
votes
9answers
9k views

Computer riddle: I treat vars like D

Little 'bout my age: far from that of B Yet in my syntax, you will find some C The way I treat vars, that is much like D I do take objects, but I'm not like E If it starts with F, you'll know ...
26
votes
8answers
2k views

Meatsacks, please help us decipher this code

Be greeted, meatsacks. We have been studying several of your species for some time now. One of the subjects, some meatsack related to saving Earth several times, seemed to know a lot of our operations ...
26
votes
1answer
1k views

Self-Description

Part of the Fortnightly Topic Challenge #35: Restricted Title 1 This text has ? l's and ? n's, but its ?th most frequent letter is f. This text also has ? letters that are used ? times or less. Its ...
26
votes
2answers
2k views

The Prognosticator

As I traveled across the web, searching far and wide, I came across an odd puzzle that made me feel awry. It foretold the future's path and predicted no tie. How could this puzzle work, and what was ...
25
votes
14answers
2k views

The master programmer and the mystical reversal

The master programmer sat at his desk, gazing into the distance, his eyes seeing, and yet unseeing. The lunch had been heavy. His reverie was interrupted by the appearance of his close colleague, ...
25
votes
2answers
2k views

Death cases of computer technician

Police found the body of a computer technician in front of his computer, with a belly wound. There was a possibility of the victim bleeding to death after being stabbed with a sharp object. There were ...
24
votes
3answers
994 views

The PSE School of Enigmatics (Part 1)

Update: I fixed up the second image, making it (perhaps) a little bit easier to crack. You leap out of your bed. Today's the day! You check your mailbox, and wow, there it is! The frayed look of the ...
23
votes
3answers
1k views

A weird website

So I recently stumbled upon a very strange website: There doesn't seem to be anything except a normal navigation-bar (which isn't working) and a cipher. Can you decrypt it? Maybe the plaintext will ...
23
votes
1answer
544 views

The life of a Knight: Conway style

So I was thinking about Conway's game of life and the ridiculous kinds of patterns that can be made (Things that move across infinite space etc) and then I thought, hey could a chess knight do this as ...
22
votes
3answers
7k views

Wife can't figure out husband's secret account password

John and Jane are married and keep a joint account at ABC Bank. They agreed that all of their income should go into the joint account. In early 2014, John started a new job at a software company, ...
22
votes
2answers
2k views

The Legend of Sally the Cow

I was looting exploring Pelagia Farm and I stole found this note in a locked chest on the ground. It seems that one of the farmhands had tried their hand at poetry. I want to know how it ends but some ...
22
votes
2answers
756 views

A Racing Heart!

This puzzle is about an athletic, hearty person. Therefore, there are 3 pieces of information hidden accordingly: For each clue, including trailing remarks such as "(2 words)", remove all numbers, ...
22
votes
1answer
785 views

Code Movie Wall

An entry in Fortnightly Topic Challenge #36: Twisted Classics 1 I'm thinking of a movie. The Connecting Wall below (click it for a bigger version) should have made guessing the movie really simple, ...
21
votes
10answers
6k views

Another idiom for computer programmers

One of my (many) mottos: ...
21
votes
6answers
2k views

Ask me this, what's my job?

My friend was talking to me about his profession and what he did for a living and I was a bit confused about what it all entailed. When I finally got fed up and asked for clarification about what he ...
21
votes
2answers
3k views

What is this mysterious image?

Recently, my friend who lives in Italy sent me an email. This was its contents: Hi, I've got some news which you should be happy about. But I've seen you around on Puzzling.SE, so I though I'd ...
20
votes
3answers
2k views

Down the Rabbit Hole

There's a secret hidden in the text below. What mind-blowing truth does it reveal? Not imaginative? Then Zeke's Clues may assist! Unsure, lad? With our patented Obscurity Clues, begin verifiably ...
20
votes
4answers
1k views

The Prison Escape Pt. 1 (THE DOOR)

You are currently escaping a prison owned by a mad scientist. As you were about to approach a large iron door that you think should be leading to the exit, a guard came out from the shadows. ...
19
votes
1answer
2k views

The great puzzle

Someone one was trying to find out something, according to the following UNIX commands. ...
19
votes
4answers
737 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.
19
votes
3answers
463 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? ...
19
votes
1answer
806 views

Oh no! A hacker has taken control of my computer!

It seems that some guy called Magick has taken over my computer. Well, there does not seem to be any harmful stuff done at least, but this picture keeps appearing on my screen. "HACKED by Magick"? ...
19
votes
2answers
491 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. ...
18
votes
5answers
1k views

‘‘Loopy’’ C loop

What is the smallest number of non-space characters that can be added in order to change the following code into a complete C program that prints  ...
18
votes
2answers
2k views

Name that Movie

The following each describe a movie title. Figure out what they are! (I'm really bad at intros.) 1. :*:*!! 2. ...