Linked Questions
39 questions linked to/from Tips for golfing in APL
44
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64
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An abundance of integers!
An Abundant number is any number where the sum of its proper divisors is greater than the original number. For example, the proper divisors of 12 are:
...
- 57k
40
votes
68
answers
6k
views
Random Capitalization
The Task
Your task is to create a program or a function that, given an input, outputs the input text with random letters capitalized, while keeping already capitalized letters capitalized.
Every ...
- 427
80
votes
30
answers
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views
Create an "H" from smaller "H"s
Challenge
Create a function or program that, when given an integer size, does the following:
If size is equal to 1, output
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- 857
32
votes
43
answers
3k
views
Is this a Permutation of 1..n
Input a non-empty array with \$n\$ positive integers. Test if the input array contains every integer in \$1\cdots n\$.
In case you prefer 0-indexed numbers, you may choose to input an array of non-...
- 28.6k
52
votes
30
answers
6k
views
Let's golf a BIBABOBU decoder
While I was traveling in the future, I noticed a funny game among kids circa 2275. When they don't want their great-great-great-great-grand parents to understand what they're saying, they use the ...
- 166k
20
votes
51
answers
2k
views
Are All the Items the Same?
Given a list of non-negative integers, return whether or not that list is all the same number.
Rules
Input and output can be taken/given in any reasonable and convenient format
Truthy/Falsey values ...
- 21k
22
votes
53
answers
3k
views
Sum square difference
The sum of the squares of the first ten natural numbers is,
\$1^2 + 2^2 + \dots + 10^2 = 385\$
The square of the sum of the first ten natural numbers is,
\$(1 + 2 + ... + 10)^2 = 55^2 = 3025\$
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- 683
27
votes
33
answers
2k
views
Rotation summation
Take a square matrix containing positive integers as input, and calculate the "rotated sum" of the matrix.
Rotated sum:
Take the sum of the original matrix and the same matrix rotated 90, 180 and ...
- 45k
18
votes
51
answers
3k
views
The max() is not enough
Intro
A friend posed this question today in a slightly different way - "Can a single [Python] command determine the largest of some integers AND that they aren't equal?".
While we didn't find a way ...
- 309
25
votes
31
answers
3k
views
"-rot" transform
Background
-rot transform (read as "minus-rot transform") is a sequence transformation I just invented. This transform is done by viewing the sequence as a stack in Forth or Factor (first ...
- 62.1k
28
votes
26
answers
3k
views
Print the sequence
21, 21, 23, 20, 5, 25, 31, 24, ?
Inspired by this Puzzle, given an integer \$n>0\$ , print out the following sequence until you reach a non-Integer (spoilered, in case you want to solve the puzzle ...
- 1,365
33
votes
27
answers
3k
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Find the nearest greater number
The task
Given any array of integers, e.g.:
[-1,476,578,27,0,1,-1,1,2]
and an index of that array (this example uses 0 based indexing, though you can use 1 based ...
- 2,721
19
votes
28
answers
2k
views
Pendulum Encoding
Given a string as an input (which can be any acceptable/convenient format in your language), implement pendulum encoding. The test cases are split into individual items (which aren't quoted) for a ...
user92069
18
votes
34
answers
3k
views
Pythagorean triples given the hypotenuse
Definition (from Wikipedia)
A Pythagorean triple consists of three positive integers a, b, and c, such that a² + b² = c².
The typical example of a Pythagorean triple is (3,4,5): 3² + 4² = 9 + 16 = 25 ...
- 17.8k
27
votes
25
answers
4k
views
ASCII art reflection
In this challenge, you will be given a text block, and you need to perform reflection on the text.
Input:
A string to be reflected. The text may not be supplied as an array whose elements are the ...
- 14.2k