Circumference of an ellipse code-golf math geometry
Challenge
Unlike the circumference of a circle (which is as simple as \$2\pi r\$), the circumference of an ellipse is hard.
Given the semi-major axis \$a\$ and semi-minor axis \$b\$ of an ellipse (see the image below, from Wikipedia), calculate ...
50-100 rep for good answers in interesting new languages
This is a bit subjective of course, but here are my criteria:
The language is fairly new, and is interesting (in my opinion)
The answer is clever, shows a lot of work put in, and shows off many features of the language (so no trivial posts...
Solve 4x4 Mastermind in exactly 5 steps code-golf puzzle-solver
Background
Mastermind is a game of code-breaking for two players. One of the players is codemaker (Alice) and the other is codebreaker (Bob).
4x4 means that the player should guess the length-4 sequence made of four alphabets (say RG...
Peel away the layers
Meta: A rework of this proposal
In this cops-and-robbers challenge, robbers must work together in order to crack cop answers by finding out which languages the cops used.
Cops
You are to write a program, which, when executed in a specific language, does one of the following:...
Choose any sequence \$a_n\$ that has the following properties:
\$a_n\$ is prime for all \$n\$;
\$a_n\$ is strictly increasing;
\$a_n\$ has an infinite number of terms;
\$a_n\$ is sparse with respect to the primes.
For the purposes of this question, we will define sparseness as follows: let \$A(...
Deserialize a binary tree breadth-first
The task here is to deserialize a binary tree breadth-first. You probably know how to do that already, but here's an example:
Input: [1, 5, 3, #, 4, 10, 2]
Tree List: [5, 3, #, 4, 10, 2]
1
Tree List: [3, #, 4, 1...
I guess you could call this the next challenge in the "Irreducible series".
Hello World
Challenge
Create a cat subject to the constraint that it is irreducible.
A cat program C is considered irreducible if there does not exist a cat (in the same programming language as C) that can be constructe...
