All Questions
12
questions
25
votes
9
answers
1k
views
Generate all groupings
Let's define a grouping as a flat list, which is either:
just 0
2 groupings followed by the literal integer 2
3 groupings ...
- 24.5k
19
votes
19
answers
5k
views
What's my PIN number?
My PIN number is 1077, but that's too difficult to remember. I know from muscle memory that it's a digit, followed by a different digit, then followed by two of the same digit, which is different to ...
- 50.2k
23
votes
13
answers
1k
views
Generalised multi-dimensional chess knight's moves
Multi-dimensional chess is an extension of normal chess that is played on an 8x8x8x8... "board".
In normal 2D chess, a knight's move is a movement by a vector of \$ \begin{bmatrix} \pm 2 \\ \...
- 24.5k
2
votes
0
answers
137
views
Dobble Double Challenge [closed]
I have a problem, which I haven't found a solution for. Solutions to the first part are well documented, but I have yet to find anyone who has solved the second part. I call this the "Dobble"...
- 121
11
votes
25
answers
3k
views
Cartesian product of a list with itself n times
When given a a list of values and a positive integer n, your code should output the cartesian product of the list with itself n ...
- 447
20
votes
8
answers
1k
views
Pick-flatten a list
Consider the process of "picking" a nested list. Picking is defined as follows:
If the argument is a list, take an element from the list at random (uniformly), and pick from that.
If the argument is ...
- 15.5k
14
votes
35
answers
1k
views
All non-ordered pairs between the elements of an array
Task:
Return an array with all possible pairs between the elements of an array.
Example
From a=["a", "b", "c", "d"]; return ...
- 435
11
votes
22
answers
2k
views
Generate all Sublist Partitions
Given a non-empty list of integers, output every possible partitioning of the list where each partition is a non-empty sublist.
So for the list [1, 2, 3, 4] the ...
- 23.4k
9
votes
4
answers
1k
views
Calculate a probability exactly
This task is about writing code to compute a probability exactly. The output should be a precise probability written as a fraction in its most reduced form. That is it should never output ...
user9206
4
votes
2
answers
330
views
Array combinatoric comparison
Introduction
You may remember sudoku, where there can only be one of each number in each row, column and block of nine.
The general idea is that if the array contains but one element, you can submit ...
- 439
6
votes
3
answers
2k
views
Compute the Join and Meet of Partitions
Background
In this challenge, a partition of a set S means a collection of nonempty subsets of S, which are mutually disjoint ...
- 42.8k
28
votes
47
answers
4k
views
Shortest power set implementation
Problem definition
Print out the powerset of a given set. For example:
[1, 2, 3] => [[], [1], [2], [3], [1, 2], [1, 3], [2, 3], [1, 2, 3]]
Each element is to ...
- 381