A note about this meta post:
I just have one example right now, but I will have three in the final.
I thought it would be interesting to have a problem about something I know a bit about. Right now it seems a bit mathy, but I wanted to ground the problem on something real. It feels more 'real-...
So, in .NET, types are either structs (stack-allocated) or classes (heap-allocated). The latest version added a new construct, the ref struct. Which is a stack-allocated struct that gets passed by reference when used as a parameter. I have no idea what the point is.
Existential Golf
Math has a lot of symbols. Some might say too many symbols. So lets do some math with pictures.
Lets have a paper, which we will draw on. To start the paper is empty, we will say that is equivalent to \$\top\$ or \$\textit{true}\$.
If we write other things on the paper they...
Is my explanation of the system clear? I know the challenge is not yet complete.
@Mego I actually have since looked it up and found that there's another restriction on ref structs: They can never appear on the heap, even as a a member of some other object. This forces them to be local variables and allows them to work more safely with stackalloc'd pointers and whatnot.
@Downgoat In Firefox it seems to draw the outline as two squares plus four rectangles plus four triangles, however when the offset causes the hole to have negative size then it just keeps moving the squares and they end up where you see them in the diagram. As for the rectangles and triangles... well, try an offset of -80px... no, I don't understand it either.
CMC: code-golf Given an edge-connected region of 1s as a rectangular binary matrix, output number of holes in it. Use O(log n) memory and O(n log n) time, in bit complexity (O(1) mem and O(n) time in word complexity).
Try to come up with an algorithm first. I guarantee that it's possible.
I just thought I had invented a great algorithm for bitshifts by a rational and started writing a sandbox post until I noticed that a << b would equal floor(a * (2**b) and it would be too trivial.
CMC: code-golf Given an edge-connected region of 1s as a rectangular binary matrix consisting of n numbers, output number of holes in it. Assume the matrix is surrounded by zeroes, and a hole is a edge-connected region of 0s inside the 1 block. Use O(log n) memory and O(n log n) time, in bit complexity (O(1) mem and O(n) time in word complexity, assume a word is O(log n) bits).
thinking again ...
I have not yet rigorously proven it. I have to find some way to make the spec so it's possible.
Assume that the piece of 1 is a 3D shape (similar to a dihedron). Then compute the number of vertices, edges, faces. Then use that to compute the genus. That's the answer.
hi.. I have an algo question. If I want to calculate the pearson correlation coefficient between two vectors of the same length it is nice and simple wikimedia.org/api/rest_v1/media/math/render/svg/…
but what if I have a short vector of length m and a long vector and I want to compute the correlation coefficient between the short vector and every subvector of the long one of length m?
Your task is, given x, output 2*x. Easy right!? But there's a catch: x will be given as a (possibly infinite) continued fraction, and the output must be a continued fraction. The input is guaranteed to be a real algebraic number whose degree is at most 2.
Input: The continued fraction of x. This...
@NewMainPosts I'm more than confident Mathematica's builtin multiplication would work, but I don't remember properly how continued fractions work to test
A note about this meta post:
I just have one example right now, but I will have three in the final.
I thought it would be interesting to have a problem about something I know a bit about. Right now it seems a bit mathy, but I wanted to ground the problem on something real. It feels more 'real-...
Existential Golf
Math has a lot of symbols. Some might say too many symbols. So lets do some math with pictures.
Lets have a paper, which we will draw on. To start the paper is empty, we will say that is equivalent to \$\top\$ or \$\textit{true}\$.
If we write other things on the paper they...
