This challenge is intended to be solved by using, manipulating, or creating shapes or other geometric structures.
17
votes
8answers
690 views
Rectangle Detection
Write a program or function that takes in a multiline string of 0's and 1's. No other characters will be in the string and the string will always be rectangular (all lines will have same number of ...
16
votes
2answers
421 views
Draw a random hexa-glyph
The above image is called a hexa-glyph. Hexa-glyphs are some cool patterns I made up while doodling during my DiffEq class. Here's how you make one:
Consider the following set of points, shaped ...
14
votes
5answers
194 views
Identify arborally satisfied point sets
An arborally satisfied point set is a 2D set of points such that, for any axis-aligned rectangle that can be formed using two points in the set as opposite corners, that rectangle contains or touches ...
7
votes
2answers
132 views
Count rectangle intersections
The Challenge
Given an arbitrary amount of rectangles, output the total count of intersections of those when drawn in a 2D plane.
An intersection here is defined as a point P which is crossed by two ...
14
votes
4answers
269 views
How far from the exterior?
Take a 2D region of space divided into axis aligned unit square elements with their centers aligned at integer intervals. An edge is said to be internal if it is shared by two elements, otherwise it ...
11
votes
3answers
262 views
Trilaterate your position
Introduction
Imagine you are on a two dimensional cartesian plane and want to determine your position on it. You know 3 points on that plane and your distance to each of them. While it is always ...
28
votes
1answer
204 views
Addition on Elliptic Curves
Addition on Elliptic Curves
Disclaimer: This does not do any justice on the rich topic of elliptic curves. It is simplified a lot. As elliptic curves recently got a lot of media attention in the ...
8
votes
7answers
282 views
Hexagon-In or Hexagon-Out?
There is a great story to tell about regular hexagons found for example in honeycombs. But this busy bee needs your help in telling him which point is inside or outside his honeypot. So, given a ...
18
votes
12answers
2k views
Calculate the volume of an object
You can determine the volume of objects based on a given set of dimensions:
The volume of a sphere can be determined using a single number, the radius (r)
The volume of a cylinder can be determined ...
7
votes
0answers
87 views
Cities: Sightlines
I'm at position (0, 0) of an infinite two-dimensional city, which is perfectly divided into blocks centered at each lattice point, some of which contain buildings. A building at a certain point (x, y) ...
18
votes
3answers
379 views
Text on a circle
Write a program or function that prints an input string around the discrete circle that has the minimum possible radius. For example, for input This is an example, your program should output:
a si ...
8
votes
1answer
164 views
Extend the line
Task
Given an image with a line on it, produce or display an image with the line extended the the line to the edge of image. The line is black and the background is white. The image size is 100x100 ...
15
votes
3answers
344 views
Where does the spaceship go?
Based on an idea suggested by Zgarb.
A spaceship is moving around a regular 3D grid. The cells of the grid are indexed with integers in a right-handed coordinate system, xyz. The spaceship starts at ...
6
votes
1answer
114 views
Test if a point is in an Icosahedron
Take as input 3 floating point numbers, which represent the x, y, z coordinates of a point. Return a truthy or falsey value indicating whether the point is inside the regular icosahedron centred at ...
13
votes
4answers
219 views
Compute the winding number
The winding number is the integer number of net counterclockwise revolutions an observer must have made to follow a given closed path. Note that any clockwise revolutions count negative towards the ...
19
votes
15answers
2k views
Hypercube elements
Write a function or program that outputs the number of each type of element (vertex, edge, face, etc.) of an N-dimensional hypercube.
As an example, the 3 dimensional cube has 1 cell (i.e. 1 ...
19
votes
23answers
2k views
Distance between two points in n-dimensional space
Here is another simple one:
The Challenge
Given two points in an n-dimensional space, output the distance between them, also called the Euclidean distance.
The coordinates will be rational ...
3
votes
4answers
167 views
Find our neighbors
You live in a rectangular neighborhood which is completely partitioned into N rectangular plots, i.e. there are no gaps or overlaps. Plots do not necessarily have the same width/height as other plots. ...
21
votes
15answers
3k views
Geometry is So Fun
Everybody loves geometry. So why don't we try and code golf it? This challenge involves taking in letters and numbers and making shapes depending on it.
The Input
The input will be in the form of ...
7
votes
5answers
736 views
Hypercube sides
Your goal is to output all the "sides" (corners, edges, faces, etc.) of an N-dimensional unit hypercube, where N is non-negative. A "side" is defined as any (N-M)-dimension surface embedded in ...
1
vote
2answers
174 views
Find the line guaranteed by Sylvester-Gallai
The Sylvester-Gallai theorem says: Suppose you have a finite list of points in the plane. Suppose further that not all of those points are collinear (lie in a single line). Then there is some line ...
32
votes
11answers
4k views
Toilet Paper Mysteries
Today you need to solve a very practical problem: How many loops do you need to have a certain number of sheets on your toilet paper roll? Let's look at some facts:
The diameter of a bare toilet ...
20
votes
3answers
433 views
Putting square pegs into square holes
I was intrigued by the design of this graphic from the New York Times, in which each US state is represented by a square in a grid. I wondered whether they placed the squares by hand or actually found ...
16
votes
1answer
152 views
Finding Exclusive Area in Circle Intersections
Here's a deceptively challenging geometry puzzle for you!
Given a circle A, and n other circles B[n], find the total area contained within A that is not within any circle of B.
Your code should be ...
10
votes
0answers
151 views
Lego Gear Train
Inspired by the Lego gear ratios challenge by Keith Randall.
I, too, plan on building a giant lego robot that will eventually be able to destroy the other robots in the never-before-mentioned ...
9
votes
3answers
410 views
Draw a Christmas Star / Stellated Dodecahedron
Paper stars are a big thing in my family at christmas, so I thought a virtual one would be cool.
Below is an image of a regular dodecahedron (from https://en.wikipedia.org/wiki/Dodecahedron, ...
28
votes
16answers
2k views
How much present did you get for Christmas?
Yes, how much, not how many...
As we all know, a large present is far better than a small one. Therefore, the value of the presents should always be measured in total volume, not number of presents, ...
16
votes
2answers
303 views
Playing Billiards
In this code golf, you will have to determine the direction of the shortest shot that hits exactly n cushions before falling into a pocket.
The billiard table is a 6 pocket pool table with the ...
3
votes
3answers
117 views
Most logical rectangle formula from numbers [duplicate]
Introduction
The task is simple. When given a number, output the most logical rectangle. To explain what a logical rectangle is, I provided some examples:
Input: 24.
All possible rectangles have ...
16
votes
3answers
446 views
Rolling the Dice
Rolling the Dice
So, I was rolling dice a while ago and thought of a challenge.
Given the cube with a net taken from input and a list of moves, find the square on the bottom at the end.
I will ...
10
votes
4answers
324 views
Point in convex hull (2D)
Background
The convex hull of a finite number of points is the smallest convex polygon that contains all of the points, either as vertices or on the interior. For more information, see this question ...
17
votes
1answer
356 views
Random Golf of the Day #6: Roll a d20
About the Series
First off, you may treat this like any other code golf challenge, and answer it without worrying about the series at all. However, there is a leaderboard across all challenges. You ...
3
votes
0answers
78 views
Is it a Regular Polygon? [closed]
A regular polygon is a polygon that is equiangular (all angles are equal in measure) and equilateral (all sides have the same length).
Your job is to find out if a given polygon is regular or not.
...
58
votes
2answers
788 views
Sprocket Science: Animating a Chain Drive System
The goal of this challenge is to produce an animation of a chain drive system, comprised of a set of sprocket gears connected together by a chain.
General Requirements
Your program will be given a ...
91
votes
70answers
14k views
Draw the national flag of France
There have been many other flag challenges posted but not one for the national flag of France. This week seems like an appropriate time.
Produce this flag in the fewest bytes possible:
The image ...
13
votes
2answers
291 views
Spherical excess of a triangle
Spherical excess of a triangle
As we all know, the sum of angles of any planar triangle is equal to 180 degrees.
However, for a spherical triangle, the sum of angles is always greater than 180 ...
12
votes
13answers
690 views
Square side pinpointing
Welcome to my first code-golf challenge! :) Let's hop right into it.
Challenge:
Given two floating point vectors, O (origin) and T (target), you have to create a program to print the values L and R ...
16
votes
7answers
773 views
Print a Pentomino Rectangle
Write a program or function that takes no input but prints or returns a constant textual depiction of a rectangle made of the 12 distinct pentominoes:
The rectangle may have any dimensions and be ...
1
vote
3answers
218 views
Area of Polygon [duplicate]
Given the number of vertices N of a convex polygon and each of their (x, y) calculate the polygon's area. vertexes are in clockwise order
You must handle all N <= 45 ,-600 <= x,y <= 600, ...
20
votes
8answers
814 views
Circular Blues
Write a program or function that takes in a positive integer N and recreates this pattern of circles scaled to fit an N×N pixel image:
This image is a valid output example for N = 946.
In ...
9
votes
7answers
213 views
Print a cube's vertices and it's covering triangles
Output coordinates of the vertices of a cube. Then, output a list of 12 triangles that will cover the cube, each triangle being a list of three vertex-indexes, consistently oriented. Output must be an ...
15
votes
17answers
2k views
Area of the triangle
Another easy challenge for you.
Your task
Write a program or function that takes the input, which contains 3 pairs of x- and y-coordinates and calculates the area of the triangle formed inside them. ...
37
votes
8answers
2k views
Can I Slide Apart The Puzzle?
Write a program or function that takes in a rectangular grid of text where every cell is either an A or a B. All the A cells will form a simply-connected shape, i.e. they will all be orthogonally ...
15
votes
3answers
396 views
Regular Polygrams
Given the number of vertices n ≥ 3 and the "step size" 1 ≤ m < n/2 (indicating the distance between two connected vertices), output a graphical representation of the corresponding regular ...
13
votes
5answers
284 views
Is it L-convex?
Background
A polyomino is called L-convex, if it's possible to travel from any tile to any other tile by an L-shaped path, that is, a path that goes in the cardinal directions and changes direction ...
2
votes
1answer
198 views
Measuring Rectangles
Challenge
Your goal is to write a program which will output the 8 measurements of a rectangle, with only some measurements in the input. Your program should throw an error if it cant be done.
Here ...
27
votes
7answers
2k views
Beatles Songs and Hexagons
Write two triangle (i.e. pyramid) shaped programs.
The first one should be an upwards pointing text triangle with a minimum base width of three characters. So it would have a structure like
X
XXX
...
13
votes
5answers
1k views
Pyramid Schemes
Mayan pyramids were (and are) an important part of ancient architecture, that were generally used for religious purposes.
They were usually step pyramids, but the steps on each were too steep to ...
16
votes
1answer
326 views
Cut a pizza into identical slices
This is what I thought this question was going to be, before I fully read it.
A group of code golfers walk into The Nineteenth Bite Pizzeria and order a pizza. It comes in an irregular shape, made ...
30
votes
12answers
4k views
Visually Explain the Pythagorean Theorem
A common visual explanation of the Pythagorean theorem is as such:
The squares are meant to represent the side length's squared, and the areas of a + b = c, just like the Pythagorean theorem says.
...
