A competition to solve a particular problem through the usage and manipulation of strings.
15
votes
35answers
3k views
Reverse stdin and place on stdout
Requirements:
Take an input on stdin including new lines / carriage returns of unlimited length (only bounded by system memory; that is, there is no inherent limit in the program.)
Output the ...
40
votes
6answers
2k views
Language Design: 2-D Pattern Matching
This is Fortnightly Challenge #6. Theme: Language Design
There's a chatroom for this challenge. Come and join us if you want to discuss ideas!
And now for something completely different...
This ...
4
votes
28answers
1k views
Implement an integer parser
Implement an integer parser in the shortest code possible, with the following restrictions:
The function or program can only take one argument: a string (or equivalent). Assume it to be signed and ...
52
votes
82answers
10k 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 ...
26
votes
4answers
2k views
9-hole mini-golf: Text Manipulation
9-hole mini-golf: Description
9 (mostly fairly easy) code golfing challenges of varying difficulty
Penalties for using the same language more than once
All challenges about a specific theme (this ...
24
votes
9answers
2k views
Word Search Puzzle
Given a rectangular text as a word search puzzle and a search string, determine if the text contains the search string. The search string may appear:
horizontally, vertically or diagonally
forwards ...
9
votes
7answers
4k views
Find the minimum edit distance between two strings
Explanation
The edit distance between two strings is a function of the minimum possible number of insertions, deletions, or substitutions to convert one word into another word.
Insertions and ...
39
votes
24answers
6k views
Draw the Sawtooth Alphabet
A simple one today. Write the shortest program that draws a "sawtooth alphabet" given a positive integer for the height. You must write the name of your programming language when you come to the ...
11
votes
19answers
3k views
Increment every number in a string
Given a string containing decimal numbers:
teststring134this 123test string54 100
increment every number in this string by one to give the new string
teststring135this 124test string55 101.
The ...
17
votes
14answers
1k views
Topographic Strings
Here is some example input, so I can explain what the problem is:
((1 2)(3 (4 5) moo)) (i (lik(cherries)e (woohoo)))
Think of this line of text as a topographic map of some mountains. Each set of ...
5
votes
4answers
501 views
Cardinal Numbers in Standard American English
Let n be any integer between 1 and 999,999 inclusive. Your challenge is to write a complete program which using stdin or command-line arguments takes in n and outputs the number of times the letter ...
12
votes
41answers
4k views
Sign that word!
What is a Word Signature?
The signature of a word are all of it's letters put in order - the signatures of this, hist and hits are all hist.
The Challenge
Write a program program should ask for an ...
11
votes
8answers
1k views
Is it a prime? w/o math
Write a program or function in any language that tells if the input is a prime number.
The input is a string representing a natural number in base-10.
The output is one of the two strings "Prime" or ...
48
votes
20answers
5k 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, ...
37
votes
5answers
3k views
Adding Numbers with Regex
I want to try a new type of regex golf challenge, which asks you to solve nontrivial computational tasks with nothing but regex substitution. To make this more possible and less of a chore, you will ...
14
votes
1answer
738 views
Fix unbalanced brackets
Consider the alphabet A ="()[]{}<>". Think of the characters in the alphabet as opening and closing brackets of 4 different types. Let's say that a string over the alphabet A is balanced if
it ...
13
votes
3answers
458 views
Burrows, Wheeler and Back
Background
The Burrows–Wheeler transform (BWT) is a reversible permutation of the characters of a string that results in large runs of similar characters for certain types of strings such as plain ...
13
votes
19answers
4k views
Outputting ordinal numbers (1st, 2nd, 3rd)
I would like to generate (as a return result of a function, or simply as the output of a program) the ordinal suffix of a positive integer concatenated to the number.
Samples:
1st
2nd
3rd
4th ...
11
votes
35answers
3k views
Display number of occurrences for every character in an input string
The code should take a string as input from keyboard:
The definition of insanity is quoting the same phrase again and again and not expect despair.
The output should be like this(not sorted in any ...
9
votes
31answers
4k views
Is string X a subsequence of string Y?
Given strings X and Y, determine whether X is a subsequence of Y. The empty string is regarded as a subsequence of every string. (E.g., '' and 'anna' are subsequences of 'banana'.)
Input
X, a ...
19
votes
19answers
3k views
Hello world!!! Fibonacci distribution
Your program should output exactly: Hello world!!! with or without linefeed after.
Your program should take no input.
Sourcecode character distribution must be correct according to:
The number of ...
14
votes
15answers
2k views
Fill In the Blanks
Input
A nonnegative integer n, and a nonempty string s containing only alphanumeric characters and underscores _.
The first character of s is not _.
The underscores of s are interpreted as blank ...
14
votes
4answers
830 views
Write a program which replaces with spaces the braces in cases where braces in places cause stasis
You are a project manager. One day, one of your programmers went insane (not your fault) and took all the expressions in the codebase and added random brackets to them, before quitting on the spot, ...
13
votes
4answers
281 views
Implement bzip2's run-length encoding
Background
After applying the BWT (as seen in Burrows, Wheeler and Back) and the MTF (as seen in Move to the printable ASCII front), the bzip2 compressor applies a rather unique form of run-length ...
9
votes
8answers
660 views
Program to Spoonerise words
A spoonerisation is swapping the first letter/pronounceable syllable of two or more words.
Example: A lack of pies = A pack of lies. Bad salad = Sad ballad (ish) :)
Challenge: Write a program to ...
7
votes
5answers
2k views
Given a string find the substring which appears most often
Write a complete program (not just a function) which using stdin takes in a string of arbitrary length (assume string-length at least one) composed only of digits 0-9 and outputs using stdout the ...
18
votes
23answers
2k views
Counter counter
In typography, a counter is the area of a letter that is entirely or partially enclosed by a letter form or a symbol. A closed counter is a counter that is entirely enclosed by a letter form or ...
2
votes
3answers
129 views
all occurences of each line from a file in another file for each line in the first file
This is a code golf problem: Say you have two files, one file s and one file h. The problem is that for each line l of s you should produce a list that contains all lines of h that contain l. By ...
109
votes
233answers
15k views
+100
“Hello, World!”
So... uh... this is a bit embarrassing. But we don't have a plain "Hello, World!" challenge yet (despite having 35 variants tagged with hello-world, and counting). While this is not the most ...
72
votes
109answers
19k views
Sing Happy Birthday to your favourite programming language
Your favourite programming language has just had a birthday.
Be nice and sing the Happy Birthday song to him (or her, if you will).
Of course you should accomplish this by writing a program in that ...
38
votes
35answers
6k views
ETAOIN SHRDLU golf
Short and sweet description of the challenge:
Based off ETAOIN SHRDLU, your challenge is to write the shortest program or function in any language that outputs the 26 letters of the English alphabet ...
41
votes
56answers
4k views
How to randomize letters in a word
According to some controversial story, the odrer of ltteres in a wrod deos not mttaer much for raednig, as lnog as the frist and lsat lteter macth with the orignial wrod.
So, for fun, what would be ...
38
votes
25answers
3k views
Fake Marquee Text
In this challenge fake marquee text is text that is shown part by part, in a scrolling-like fashion.
Some examples:
testing 4
t
te
tes
test
esti
stin
ting
ing
ng
g
hello 2
h
he
el
ll
lo
o
...
32
votes
14answers
3k views
Staircase writing
Write a program or a function that will output a given string in a staircase fashion, writing each part of a word that starts with a vowel one line below the previous part.
For example:
Input: ...
36
votes
40answers
7k views
The shortest code to invert a binary string
Me thinks there aren't enough easy questions on here that beginners can attempt!
The challenge: Given a random input string of 1's and 0's such as:
10101110101010010100010001010110101001010
Write ...
15
votes
23answers
2k views
Sign that word 2!
Sign that word 2!
Not that long ago, I posted a challenge called Sign that word!. In the challenge, you must find the signature of word, which is the letters put in order (e.g. The signature of this ...
13
votes
24answers
2k views
Convert a string to its Rövarspråket equivalent
Rövarspråket
Rövarspråket is a word game played by Swedish children, from the books about Kalle Blomkvist by Astrid Lindgren.
The basic rules are as follows (from Wikipedia):
Every consonant ...
40
votes
7answers
3k views
Avoiding Rivers
Background
In typography, rivers are visual gaps in a block of text, which occur due to coincidental alignment of spaces. These are particularly annoying since your brain seems to pick them up more ...
20
votes
18answers
2k views
Swap capitalization of two strings
your shift key is broken. wheNever you type two lines, the cApitaL
LetteRs in them get swappeD. you must write a program to fiX THIS!
Description
The input is two strings, s1 and s2, equal in ...
17
votes
14answers
2k views
Determine a string's Scrabble score and validity
Your task is to determine if a given string is of proper length and can be represented with Scrabble tiles and, if so, output the sum of each letter's score.
If you don't know how to play Scrabble:, ...
15
votes
1answer
847 views
Rearranging Words
You should write a program which receives two strings as input and outputs a sequence of movements which rearrange the first string into the second. You should use as few moves as you can.
Both ...
15
votes
36answers
2k views
Shortest program to split a string at non-digits without RegExps
EDIT: If you're using Lisp, I have given some guidelines at the bottom in counting bytes.
Objective: Make the shortest function that splits a string at non-digits and returns an array consisting of ...
10
votes
15answers
3k views
Is 7 l8r than 9? (Is seven later than nine?)
This is a fairly simple code golf challenge. Your program, given an ASCII string, is to parse that string into two strings, which it will evaluate. If the second string is "later" than the first one, ...
10
votes
6answers
537 views
Print an ascii spiral in O(log n) memory
You may write a program or function that receives an odd, positive integer n, where n >= 3, as either a function argument, command line arguments, or on STDIN (or equivalent for your system), and ...
8
votes
8answers
545 views
Cambridge Transposition
I'm sure most, if not all, of you have come across this at some point or another:
Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer
in waht oredr the ltteers in a wrod are, ...
19
votes
3answers
1k views
Distinguish between Masculine and Feminine Nouns in French within 100 characters
You are to write a very small program within 100 characters. Your program must distinguish between masculine and feminine french nouns. The output should be un if it is masculine and une if it is ...
18
votes
7answers
609 views
Move to the printable ASCII front
Background
The move-to-front transform (MTF) is a data encoding algorithm designed to improve the performance of entropy encoding techniques.
In the bzip2 compression algorithm, it is applied after ...
15
votes
3answers
299 views
Toggle, Print, Repeat
This challenge is loosely inspired by the unimplemented esolang Pada.
Consider an array of 8 bits, all initialised to zero. We'll introduce a very minimalistic instruction set to print arbitrary ...
14
votes
14answers
2k views
QuickGolf - Ignore the noise #1
Instructions
Barry is a not so good backend developer in charge of a small API that should give you information about purchases made in a client's shop. However, he hasn't done a great job and your ...
14
votes
9answers
1k views
Write a function that returns past tense of given verb
Challenge
Write a function which takes an argument which is a verb, and returns the past tense of the verb. (Assume that the verb is regular)
Past tense
Note: consider y as neither consonant ...
