Questions tagged [restricted-source]
Imposes a restriction on the source code used to solve the challenge, for example, having no numbers in the source code.
308
questions
590
votes
287answers
219k views
Produce the number 2014 without any numbers in your source code
Note to challenge writers as per meta consensus:
This question was well-received when it was posted, but challenges
like this, asking answerers to Do X without using
Y
are likely to be poorly ...
236
votes
119answers
33k views
Without using numbers, get the highest salary you can. But don't exaggerate!
As I'm applying for some jobs whose job advert doesn't state the salary, I imagined a particularly evil interviewer that would give the candidate the possibility to decide their own salary ...by "...
218
votes
24answers
21k views
DISARM THE B.O.M.B.!
You have been hired for your tech knowledge as a Secret Agent's sidekick to ensure that the good guy can get his job done and the world can be saved.
This is your last mission before retiring with a ...
162
votes
66answers
23k views
How high can you count?
Challenge:
Your task is to write as many programs / functions / snippets as you can, where each one outputs / prints / returns an integer. The first program must output the integer ...
128
votes
129answers
39k views
Obfuscated Hello World
Create the shortest possible obfuscated program that displays the text "Hello World".
In order to be considered an obfuscated program, it must meet at least two of the following requirements:
Does ...
124
votes
58answers
17k views
Fewest (distinct) characters for Turing Completeness
Summary:
For any given language, what is the smallest amount of unique characters for your language to be Turing-Complete?
Challenge:
For any language of your choice, find the smallest subset of ...
120
votes
95answers
22k views
ASCII's 95 Characters…95 Movie Quotes
Update: The winner has been decided, but the challenge is not over!
Finally, nearly 3 months after the question first started, someone has remained the last answerer for more than a week! ...
117
votes
73answers
25k views
Largest Number Printable
Your goal is to write a program that prints a number. The bigger the number, the more points you'll get. But be careful! Code length is both limited and heavily weighted in the scoring function. Your ...
109
votes
67answers
26k views
I'm a palindrome. Are you?
There have been a couple of previous attempts to ask this question, but neither conforms to modern standards on this site. Per discussion on Meta, I'm reposting it in a way that allows for fair ...
90
votes
23answers
11k views
Programming a Pristine World
Let's define a pristine program as a program that does not have any errors itself but will error if you modify it by removing any contiguous substring of \$N\$ characters, where \$1 \le N < \text{...
89
votes
33answers
16k views
Eww, those bytes are gross
Write a program or function that, when given a string, filters out as many distinct bytes as it can and returns the cleaned string. However, since your program hates them, none of these bytes can be ...
89
votes
50answers
9k views
Find an Illegal String
The challenge is to find a string of characters that cannot appear in any legal program in your programming language of choice. That includes comments, strings, or other "non-executable" parts.
...
86
votes
20answers
7k views
Pristine and Unique Code Bowling
Your challenge is simple: write as long of a pristine program as possible in the language of your choice using only unique bytes. (The full definition of a pristine program, copied from that link, is ...
85
votes
132answers
46k views
Loop without 'looping' [closed]
A question similar to this has been asked a couple of years ago, but this one is even trickier.
The challenge is simple. Write a program (in your language of choice) that repeatedly executes code ...
80
votes
72answers
15k views
Hello world! with limited character repetition
In a language of your choice, write a program that exactly outputs the characters Hello world! followed by a newline. The code:
should not use any character more ...
80
votes
102answers
13k views
Hello World 0.0!
source: Dilbert, September 8, 1992
I'm hoping to add a new twist on the classic "Hello World!" program.
Code a program that outputs Hello World! without:
String/...
76
votes
183answers
19k views
The Letter A without A
Your task is to display the letter "A" alone, without anything else, except any form of trailing newlines if you cannot avoid them, doing so in a program and/or snippet. Code that returns (instead of ...
76
votes
37answers
12k views
Non-discriminating Programming
We say a string is non-discriminating if each of the string's characters appears the same number of times and at least twice.
Examples
"aa!1 1 !a !1" is non-...
72
votes
117answers
15k views
Print the alphabet without using each vowel
Inspiration: in 1939, a man named Ernest Vincent Wright wrote a novel called Gadsby without using the letter 'e'.
Your task is to write a set of (up to 5) programs in any language (which has a text-...
72
votes
24answers
4k views
Tweetable hash function challenge
In this code-challenge you will write a hash function in 140 bytes1 or less of source code. The hash function must take an ASCII string as input, and return a 24-bit unsigned integer ([0, 224-1]) as ...
70
votes
27answers
6k views
2016 Time Capsule String: How Versatile Is Your Language?
About a year ago on Dec 31, 2015, I had the idea that:
We should make a time capsule string. Everybody gets to add one character and next new years we'll see who can make the best program out of all ...
69
votes
81answers
7k views
Three-Three-Three!
Write a program that produces an output such that:
At least three distinct characters appear.
The number of occurrences of each character is a multiple of 3.
For example, ...
69
votes
79answers
6k views
No strings (or numbers) attached
If you like this, consider participating in:
The Official Dyalog APL 2016 Year Game
The monthly Dyalog APL 2017 Code Golf Challenge
Make 12 snippets/expressions, in the same language, that result in ...
65
votes
20answers
7k views
Just repeat yourself
Write a program that outputs
Do not repeat yourself!
Your program code must respect the following constraints :
its length must be an even number
each ...
65
votes
11answers
3k views
Only Even Bytes
The scenario
Lately you have been noticing some strange behavior with your favorite text editor. At first it seemed that it was ignoring random characters in your code when writing to disk. After a ...
64
votes
20answers
8k views
Hash collision: “NO” means “YES”
This Code Golf was inspired by the recent Daily WTF article You Can't Handle the True!, which features a string comparison written as:
...
63
votes
61answers
9k views
Write lines in detention
Introduction
Bad news guys - you got detention. Your English teacher doesn't understand this site and wants you to "stop doing math on your digital dohickeys, this is English class!"
She ...
58
votes
156answers
8k views
Output your Score!
Challenge:
The concept is simple enough: write a full program to output its own code golf score!
Output should only be the byte count of your program and a trailing ...
56
votes
39answers
16k views
All Your Base Are Belong To Us (Restricted)
Input must not be required, and output must read "All your base are belong to us".
Restrictions
No external resources.
Plus a minimum of two of the ...
56
votes
50answers
11k views
Print every printable ASCII character without using it
In a programming language of your choice, write 95 programs, each of which outputs a different one of the 95 printable ASCII characters without that character occurring anywhere in the program.
For ...
55
votes
20answers
8k views
Exit Code Golfing
Inspired by this default for IO.
The Task
Write a program that, given an input integer x between 0 and 255, crashes with exit code ...
55
votes
31answers
9k views
Output the text “Code Bowling”
Code-Bowling
You've been hired by Brunswick Bowling to create a simple program to output the text Code Bowling on their monitors. This company is worth a pretty ...
55
votes
24answers
6k views
Significant Whitespace
We define whitespace to be any of the three characters, tab (0x09), newline (0x0A) or space (0x20).
For this challenge, you're to write two programs or functions in the same programming language, ...
54
votes
7answers
8k views
Duct tape can fix Mother's Day
Based on the Duct tape can fix anything question, that was too broad, with very similar rules. Only this time the objective is very specific:
The challenge
Your mission is to make a program that ...
54
votes
15answers
4k views
Write the whole of the holed using the unholed
The ASCII characters from decimal code 33 to 126 are:
!"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
...
52
votes
30answers
11k views
Print the phrase “And she said, 'But that's his.'” using only the alphabet
Print the phrase And she said, 'But that's his.' using only the following characters: ...
52
votes
90answers
9k views
Print X without X (cop's thread)
This is the cop's thread of a cops-and-robbers challenge. You can view the robber's thread here
A pretty common beginner style question is to print some string, but, there's a catch!, you need to do ...
52
votes
32answers
4k views
Does it Lead or Follow?
In this challenge you are to write a program or function, that takes a string as input and outputs one of two possible values. We will call one of these values truthy and one falsy. They do not need ...
50
votes
44answers
7k views
Print all ASCII alphanumeric characters without using them
Challenge
Print the following characters:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890
The catch is that you may not use any one of them in ...
50
votes
66answers
11k views
Divide a number by 3 without using *, /, +, -, % operators [closed]
Quoting this question on SO (Spoiler alert!):
This question has been asked in an Oracle interview.
How would you divide a number by 3 without using *, /, +, -, %,
operators?
The number ...
50
votes
72answers
15k views
yes is 91 lines long
yes, from coreutils, is 91 lines long. Many of them are comments, but that is still WAY too long.
Edit from September 2019: the source file grew over the past five ...
50
votes
31answers
7k views
Conway's Monster
This challenge is in honor of mathematician John Conway who passed away April 11, 2020 due to COVID-19. He was famous for coming up with the Game of Life cellular automaton and many other mathematical ...
49
votes
41answers
16k views
Obfuscated FizzBuzz Golf [closed]
Create the shortest possible obfuscated FizzBuzz implementation.
To be considered obfuscated, it should satisfy at least one of the following:
Does not contain any of the words "Fizz", "Buzz", or "...
49
votes
66answers
6k views
Depalindromize this string!
Given a palindrome generated according to this challenge, depalindromize it.
Test cases
...
48
votes
2answers
2k views
JSF**k with only 5 symbols?
This is not a challenge but a question, I figured it was on topic because of
Non-challenge questions that are related to solving programming puzzles or a particular type of challenge are also on ...
47
votes
14answers
7k views
Make a code square with your favorite word
Pick your favorite 6 letter common English word that has no repeated letters, such as wombat.
Write a program in an N×N grid of characters without comments such ...
47
votes
17answers
7k views
DON'T… do NOT lowercase UPPERCASE this!
Write a program that outputs its input unchanged. However:
If all uppercase characters are removed from the program, it lowercases all uppercase letters.
If all lowercase characters are removed from ...
46
votes
138answers
14k views
Output programming language name
Challenge:
In the programming language of your choice, take no input and output your programming language's name.
Fair enough, right?
Restrictions:
You can't use any character that is included in ...
46
votes
50answers
7k views
Rock Around the Clock
In as few Unicode characters as possible, print the following (144 characters):
...
46
votes
5answers
2k views
Multiply with restricted operations
There's a 500 rep unofficial bounty for beating the current best answer.
Goal
Your goal is to multiply two numbers using only a very limited set of arithmetic operations and variable assignment.
...
