instruction_seed stringlengths 292 48.7k | found_ngrams listlengths 0 21 |
|---|---|
Introduction
This is a log of length 5:
#####
I want to pile a bunch of these logs on top of each other.
How I do this is that I slide a new log onto the topmost one from the right, and stop sliding when their left or right ends align (don't ask why).
If the new log is longer, it slides all the way to the left end of ... | [] |
Background
We all know the famous Fibonacci sequence, where each term is the sum of the previous two, with the first term being 0 and the second one being 1. The first few elements are:
0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765
What we are going to implement today is a si... | [
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],
[
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220,
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220,
18,
11,
220,
20
],
[
11,
220,
16,
11,
220,
17,
11,
220,
18,
11... |
Specifications
For this challenge, you will be given a matrix of some sort in any reasonable format for a 2-D array. For each row except the last, in order from top (first) to bottom (last), rotate the row below it by x to either direction (you choose a consistent direction to use) where x is the first element in the c... | [] |
Based on this Math.SE question; number copied from this answer. Number originally from a Numberphile video, of course.
Your task is to output the following 1350-digit prime number:
8888888888888888888888888888888888888888888888888888888888888888888888888888888888888888888881111111111111111111111118888881111111111111111... | [] |
This is how the Kolakoski sequence (OEIS A000002) is defined:
The Kolakoski sequence is a sequence that contains 1 and 2, and the nth element of the sequence is the length of the nth group of equal elements (run) in the sequence itself. The first 20 terms of the sequence and the respective lengths are:
1 2 2 1 1 2 1 2... | [] |
Background
The deltas of an array of integers is the array formed by getting the differences of consecutive elements. For example, [1, 2, 4, 7, 3, 9, 6] has the following deltas: [1, 2, 3, -4, 6, -3].
We will now define the deltas of a matrix of integers as the deltas of each row and each column it contains.
As an exam... | [] |
Inspired by this
In the linked challenge, we are asked to apply addition to the elements of the original and the reverse of the input array. In this challenge, we are going to make it slightly more difficult, by introducing the other basic math operations.
Given an array of integers, cycle through +, *, -, //, %, ^, wh... | [
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In math, one way to figure out what the type of a given relation (linear, quadratic, etc) is to calculate the differences. To do so you take a list of y values for which the gap between the correspondent x values is the same, and subtract each one from the number above it, creating a list of numbers one shorter then t... | [] |
Specs
You have a cubic 3D space x,y,z of size S integer units, such as 0 <= x,y,z <= S.
You get from default input methods an array of points P represented as x,y,z integer coordinates, in any reasonable format as you like, for example: [x1,y1,z1],[x2,y2,z2],[x3,y3,z3] ... [xn,yn,zn].
All the P values will be in the ... | [] |
Given a rectangular matrix of elevations, draw its contours.
Task
Two elements x and y are on the same contour level if floor(x/10) == floor(y/10). For example, 52 and 58 are on the same contour level, but 58 and 64 are not.
The act of drawing contours is defined as follows:
For every element e, replace it with a two-c... | [] |
I have a stupid old alarm clock with two buttons: hour and minute. The hour button increments the hour of a set alarm, and minute increments the minute time of a set alarm. However, some smart designers realized that pressing both buttons at the same time should have a meaning, and decided that pressing hour and minute... | [] |
We have a floating point number r between 0 and 1, and an integer p.
Find the fraction of integers with the smallest denominator, which approximates r with at least p-digit precision.
Inputs: r (a floating point number) and p (integer).
Outputs: a and b integers, where
a/b (as float) approximates r until p digits.
b... | [] |
Your challenge today is to take an array, split it into chunks, and add those chunks.
Here's how this works: Your program or function will be given an array of integers a and a chunk size L. The array should be split into arrays of size L, if the array length is not divisible by L then the array should have 0's appende... | [] |
An insignificant array is an array of positive integers, where the absolute differences between consecutive elements are all smaller than or equal to 1.
For example, the following array is insignificant:
[1, 2, 3, 4, 3, 4, 5, 5, 5, 4]
Because the corresponding (absolute) differences are:
[1, 1, 1, 1, 1, 1, 0, 0, 1]
W... | [
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],
[
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220,
19,
11,
220,
20
],
[
11,
220,
17,
11,
220,
18,
11,
220,
19,
11... |
Let me introduce you to GAU numbers
GAU(1) = 1
GAU(2) = 1122
GAU(3) = 1122122333
GAU(4) = 11221223331223334444
GAU(6) = 11221223331223334444122333444455555122333444455555666666
...
GAU(10) = 112212233312233344441223334444555551223334444555556666661223334444555556666667777777122333444455555666666777777788888... | [] |
Introduction
You can skip this part if you already know what a cyclic group is.
A group is defined by a set and an associative binary operation \$\times\$ (that is, \$(a \times b) \times c = a \times (b \times c)\$. There exists exactly one element in the group \$e\$ where \$a \times e = a = e \times a\$ for all \$a\$ ... | [] |
Inspired by Generate Keyboard Friendly Numbers.
Background
Many number pads have the following layout:
789
456
123
0
We define a number's neighborhood as the set of cells orthogonally adjacent to it on the numpad shown, including itself. For example, 2's neighborhood is {1,5,3,0,2} and 0's neighborhood is {1,2,... | [
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Challenge
Given a binary matrix and a binary string, determine if that binary string can be found starting at any point in the matrix and moving in any direction at any subsequent point to form the binary string. That is, can the string be found folded up however inside the matrix?
The string can only be folded at 90 d... | [] |
While doodling around with numbers, I found an interesting permutation you can generate from a list of numbers. If you repeat this same permutation enough times, you will always end up back at the original array. Let's use the following list:
[1, 2, 3, 4, 5]
as an example
Reverse the array. Now our array is
[5, 4, 3,... | [
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],
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Take two inputs, a non-empty vector/list containing digits 1 and 2 and a string (no, you may not take 0/1 instead). The string will be one of the following (in lowercase, exactly as written below:
increasing
decreasing
ones
twos
all
none
If the string is ____ then you shall return the indices ___:
increasing ... wher... | [
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],
[
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18,
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Given two positive integers a and b, output the frequency distribution of rolling a b-sided die a times and summing the results.
A frequency distribution lists the frequency of each possible sum if each possible sequence of dice rolls occurs once. Thus, the frequencies are integers whose sum equals b**a.
Rules
The fre... | [
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],
[
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18,
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19,
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220,
20,
11
]
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You deal cards labeled 0 to 9 from a deck one a time, forming stacks that start at 0 and count up by 1.
When you deal a 0, you place it on the table to start a new stack.
When you deal any other card, you stack it atop a card that's exactly
one lower in value, covering it. If there's no such card, the deck isn't stac... | [
[
11,
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11,
220,
19,
11,
220,
20,
11
]
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I guess I'm not the only one who have seen this kind of image on Facebook (and other sites).
The picture above was posted 16 days ago, and has accumulated 51 k comments. Some answers: 0, 4, 8, 48, 88, 120, 124 and so on.
Challenge:
The mathematics in the question doesn't make sense1, so we can't find the correct answ... | [] |
Introduction:
We all know these three basic arithmetic math tables I assume.
ADDITION:
+ | 1 2 3 4 5 6 7 8 9 10
----------------------------------
1 | 2 3 4 5 6 7 8 9 10 11
2 | 3 4 5 6 7 8 9 10 11 12
3 | 4 5 6 7 8 9 10 11 12 13
4 | 5 6 7 8 9 10 11 12 13 14
5 | 6 7 8 9 10 11 ... | [] |
Given a positive integer n output the n-th number of the euro-iginal sequence.
Calculating the Sequence
This sequence is equal to OEIS A242491.
A number is part of said sequence if the number can be made up by using as many different euro coins or notes, but only one of each. Note that you don't have to consider cents.... | [
[
11,
220,
16,
11,
220,
17,
11,
220,
18,
11,
220,
20,
11
]
] |
Let's imagine we have a matrix of bits (which contains at least one 1):
0 1 0 1 1 0 1 0 0 1 0
0 1 0 1 0 0 1 0 1 1 0
0 0 1 0 1 1 0 1 0 1 0
1 1 0 0 1 0 0 1 1 0 1
0 0 0 1 0 1 1 0 0 1 0
We want to set some of the bits in this matrix such that it forms a contiguous blob of 1s, in which every 1 is directly or indirectly con... | [] |
Take an input list L containing positive integers, and insert the least amount of integers into the sequence, so that you make it a continuous one.
Example:
L = 4 2 6 1
Out: 4 3 2 3 4 5 6 5 4 3 2 1
The input and output formats are optional.
Test cases:
L = 1
Out: 1
L = 10 4
Out: 10 9 8 7 6 5 4
L = 13 13
Out: 13 13
... | [] |
Take two positive integers N and M and create the concatenated cumulative sums of [N], with M iterations. Output the result of the last iteration.
Definition of the concatenated cumulative sum:
Start with a number N and define a sequence X = [N]
Append to X the cumulative sums of X
Repeat step 2 M times.
The cumulati... | [
[
11,
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20,
11
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For the purpose of this challenge, a Prime Power of a Prime (PPP) is defined as a number that can be defined as a prime number to the power of a prime number. For example, 9 is a PPP because it can be represented as 3^2. 81 on the other hand is not a PPP because it can only be represented as 3^4, and 4 is not prime. ... | [] |
If Abe goes, then Beth and Diana go. If Beth goes, then Catherine goes. If Catherine goes, then Diana goes. If Diana goes, then Ezra goes. Only three people go. Who goes?
Challenge
Given a list of several pairings of people, such that in each pairing the second person goes if the first person goes, and a positive integ... | [] |
There have been a lot of prime-/prime factorization-related challenges recently, so I thought it might be interesting to go the other way.
Given:
a positive integer n, and
a non-empty list of positive integers f
write a full program or a function to find the smallest integer i such that i >= n and i is a product of n... | [
[
20,
11,
22,
11,
16,
16,
11,
16,
18,
11,
16,
22,
11
],
[
18,
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11,
16
],
[
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11,
... |
Consider a bridge of length B formed by tiles labeled with the digits of the positive integers concatenated. For example, if B was 41, then it would look like this:
-----------------------------------------
12345678910111213141516171819202122232425
Now imagine a train of length T crossing the bridge. The leftmost poi... | [
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22,
488,
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23,
488
],
[
20,
488,
220,
21,
488,
220,
22,
488,
... |
For the purpose of this challenge, a multi-base prime is a prime which, when written in base 10, is prime in one or more bases smaller than 10 and larger than 1 as well. All single-digit primes are trivially multi-base primes. 11 is also a multi-base prime, as 11 in binary is 3, which is prime (it is also prime in ba... | [
[
11,
18,
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11
]
] |
The binary-square-diagonal-sequence is constructed as follows:
Take the sequence of positive natural numbers: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, ...
Convert each number to binary: 1, 10, 11, 100, 101, 110, 111, 1000, 1001, 1010, 1011, 1100, 1101, 1110, 1111, 10000, 10001, ...
Concatenate them: ... | [
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],
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11,
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],
[
220,
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17,
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18,
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This is Hole-1 from The Autumn Tournament of APL CodeGolf. I am the original author of the problem there, and thus allowed to re-post it here.
Given a list of numbers, produce a horizontal bar chart of # characters for how many numbers fit into each of ten equal-sized groups. For example, if the data ranges from 0-100... | [] |
A000330 - OEIS
Task
Your task is simple, generate a sequence that, given index i, the value on that position is the sum of squares from 0 upto i where i >= 0.
Example:
Input: 0
Output: 0 (0^2)
Input: 4
Output: 30 (0^2 + 1^2 + 2^2 + 3^2 + 4^2)
Input: 5
Output: 55 (0^2 + 1^2 + 2^2 + 3^2 + 4^... | [] |
Definition and Rules
A golfy array is an array of integers, where each element is higher than or equal to the arithmetic mean of all the previous elements. Your task is to determine whether an array of positive integers given as input is golfy or not.
You do not need to handle the empty list.
Default loopholes apply.... | [
[
16,
11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20
]
] |
This is Hole-9 from The Autumn Tournament of APL CodeGolf. I am the original author of the problem there, and thus allowed to re-post it here.
Given a simple (rectangular, non-jagged) Boolean array (of one or more dimensions) return a list of thusly shaped arrays where the first array is identical to the input and the... | [] |
Life-like cellular automaton are cellular automaton that are similar to Conway's Game of Life, in that they operate on a (theoretically) infinitely large square grid, where each cell has exactly 8 neighbours, and is one of 2 states, namely alive and dead.
However, these Like-like versions are different in a crucial way... | [] |
We are searching for a sequence
Take the natural numbers
1,2,3,4,5,6,7,8,9,10,11,12,13,14...
Convert to base-2
1,10,11,100,101,110,111,1000,1001,1010,1011,1100,1101,1110...
Concatenate the above numbers
110111001011101111000100110101011110011011110...
Partition this number in Prime-Chunks
(chunks containing a prime num... | [
[
11,
18,
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11
],
[
18,
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11,
16
],
[
11,
20,
11,
22,
11,
16,
16,
11,
16,
18,
11,
... |
Consider the array of positive integers:
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, ...
Then, concatenate them:
1234567891011121314151617181920212223242526...
And then split them into chunks of variable length, each length being equal to the Nth positive integer:
[1][23][456][7891][01112][131415][1617181][92021222][3... | [
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Task
Your task is to output a single integer, with one restriction: its digits must be a permutation of [1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6].
For example, you could output 653443653152432, 413265345463352, or any of the other 15-digit integers whose digits are a permutation of the list.
Rules
Your code must t... | [] |
This is the PPCG Prime
624 digits long
77777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777777711111111111111111111111111111111111111111111111111111111111111111111111111111118888888811888888881118888881118888881118811111... | [] |
Non-math explanation
This is an explanation that is meant to be approachable regardless of your background. It does unfortunately involve some math, but should be understandable to most people with a middle school level of understanding
A pointer sequence is any sequence such that \$a(n+1) = a(n-a(n))\$.
Lets pick apar... | [] |
iOS 11 has a bug that makes the result of 1+2+3 to be 24. This is related to the animation speed, but anyway:
The task is to make 1 + 2 + 3 == 24. But only that. So you should provide a function that correctly sums most sequences but returns 24 when the arguments are 1, 2 and 3 in any order.
Example inputs:
1 2 => 3
3 ... | [] |
Challenge
Given a list, determine if grouping the list into runs of increasing and decreasing elements will result in a list of equal-sized lists.
In other words, "turning points" of the list are spaced out evenly.
Example
Here's an example: 0, 3, 7, 5, 2, 3, 6
0, 3, 7 increases, 7, 5, 2 decreases, and 2, 3, 6 increase... | [] |
Note: This is #3 in a series of array-manipulation challenges. For the previous challenge, click here.
Moving Average of a List
The moving average of a list is a calculation resulting in a new, smoothed out list, created by averaging small overlapping sublists of the original.
When creating a moving average, we first... | [
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17,
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18,
11,
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19,
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220,
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],
[
11,
220,
17,
11,
220,
18,
11,
220,
19,
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220,
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11
]
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If we define a Fibonacci-like sequence as fk(n) = (fk(n-1) + fk(n-2)) % k, for some integer k (where % is the modulo operator), the sequence will necessarily be cyclic, because there are only k2 different values for (fk(n-1), fk(n-2)). However, this cycle doesn't usually include all possible pairs of values, so dependi... | [
[
220,
16,
11,
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16,
11,
220,
17,
11,
220,
18,
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]
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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 not a list, simply return it.
An example implementation in Python:
import random
def pick(obj):
if isinstance(obj, ... | [] |
Challenge:
Output all distinct permutations of a, potentially long, list of positive integers. You may assume that the vector has less than 1,000 numbers when testing, but the process should in theory work for any vector with more than one number regardless of size.
Restrictions:
You must restrict the memory usage to ... | [
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17,
11,
220,
18,
11,
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],
[
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11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20
],
[
11,
220,
17,
11,
220,
18,
11,
220,
19,
11... |
Title is made up, from 'Sequence Index Digit Not'.
Challenge:
Given an integer n which is >= 0, output the n'th number of the following sequence.
Here are the first 50 items, with it's (0-indexed) index above it:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 ... | [] |
Final Result
The competition is over. Congratulations to hard_coded!
Some interesting facts:
In 31600 out of 40920 auctions (77.2%), the winner of the first round won the most rounds in that auction.
If example bots are included in the competition, the top nine places won't change except that AverageMine and heurist ... | [] |
Consider the following sequence:
1, 0, 1, 2, 4, 1, 6, 8, 0, 1, 2, 4, 6, 8, 1, 0, 2, 4, 6, 8, 1, 0, 2, 4, 6, 8, 0, 1, ...
The even digits start from 0 and are grouped into runs of increasing length. They are arranged cyclically, meaning that they are sorted in ascending order until 8 is reached, and then cycled back fr... | [] |
Rectangle covers
Suppose you have a matrix of bits, for example the following.
1 1 0 0 0 1 1 0
1 1 1 1 0 1 1 1
0 1 1 1 0 1 1 1
1 1 0 1 1 1 1 0
1 1 0 1 1 1 0 1
We would like to find a rectangle cover for this matrix.
It is a set of rectangular subsets of the matrix that don't contain any 0s, but together contain all th... | [] |
Introduction
Every rational number between 0 and 1 can be represented as an eventually periodic sequence of bits.
For example, the binary representation of 11/40 is
0.010 0011 0011 0011 ...
where the 0011 part repeats indefinitely.
One way of finding this representation is the following.
Start with r = 11/40, then rep... | [] |
BCD difference
Given an integer n, convert it to BCD (binary-coded decimal) by replacing each decimal digit with its 4-digit binary representation
234 -> 0 0 1 0 0 0 1 1 0 1 0 0
Then rotate the list of binary digits in order to find the largest and smallest numbers, representable by this list without other rearrange... | [] |
A deck of cards is the Cartesian product of S suits and R ranks.
Many, though not all, card games use S=4 and R∊{6,8,13}.
A hand of H cards is dealt from the deck.
Its distribution, a.k.a. "hand pattern", is an array that describes
how many cards you got from each suit, ignoring suit order (so, it's like a multi-set).
... | [] |
Given a finite arithmetic sequence of positive integers with some terms removed from the middle, reconstruct the whole sequence.
The task
Consider an arithmetic sequence: a list of positive integers in which the difference between any two successive elements is the same.
2 5 8 11 14 17
Now suppose one or more integers... | [] |
One of my favorite definitions of the prime numbers goes as follows:
2 is the smallest prime.
Numbers larger than 2 are prime if they are not divisible by a smaller prime.
However this definition seems arbitrary, why 2? Why not some other number?
Well lets try some other numbers will define n-prime such that
n is t... | [
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[
11,
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22,
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11,
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18,
11,
... |
The Challenge
There are N cities aligned in a straight line. The i-th city is located A[i] kilometers to the right of the origin. No two cities will be in the same place.
You are going to build an electrical grid with some power plants. Power plants must be built inside a city. However, you are only allowed to build K ... | [] |
Introduction
Mathematicians often work with number sets. These are groups of numbers that share common properties. These are number sets are, in order from most specific to most broad:
Natural numbers (symbol N): These are the counting numbers: 1, 2, 3, ...
Integers (symbol Z): These are all the numbers with... | [] |
Next >>
Descriptive Keywords (for searching): Make Two Matrices Equivalent, Overlap, Array, Find
Challenge
Santa has had a history of elves stealing presents from his vault in the past, so this year he designed a lock that is very hard to crack, and it seems to have kept the elves out this year. Unfortunately, he has l... | [] |
<< Prev Next >>
Challenge
Now that Santa has finally figured out how to get into his present vault, he realises that somehow the elves got in there before him and stole some of his presents! They haven't figured out how to leave the vault yet though, so Santa has to try and catch them all. Santa and the elves both have... | [] |
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Unfortunately, Santa was not able to catch the elves in time! He has to go back to manufacturing presents now. Since the elves are definitely not Santa's slaves, he has to figure out the expenses for how much to pay them.
Challenge
Given some information for the presents, determine the cost of manufactu... | [] |
A traditional Western die is a cube, on which the integers 1 to 6 are marked on the faces. Pairs that add to 7 are placed on opposite faces.
As it is cube, we can only see between 1 and 3 faces (inclusive)1 at any given time. Opposite faces can never be seen at the same time.
Your task is to write a program or function... | [
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[
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17,
11,
220,
18,
11,
220,
19,
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11
]
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<< Prev Next >>
Thanks to the PPCG community, Santa has managed to remanufacture all of his presents and after the assembly line, the presents are now ready to be moved into the transport docks!
Each of Santa's transport docks only holds a range of present sizes because the transport sleighs are specialized for a speci... | [
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[
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]
] |
A half-exponential function is one which when composed with itself gives an exponential function. For instance, if f(f(x)) = 2^x, then f would be a half-exponential function. In this challenge, you will compute a specific half-exponential function.
Specifically, you will compute the function from the non-negative integ... | [] |
<< Prev Next >>
After some careful analysis, Santa was able to determine the dock size ranges and get the presents into the correct transportation dock.
Now, he needs you to help him balance out the transportation carts and place the presents in them in the most balanced fashion.
Challenge
You will be given the size of... | [] |
A follow-up to this challenge
Given a set of mixed dice, output the frequency distribution of rolling all of them and summing the rolled numbers on each die.
For example, consider 1d12 + 1d8 (rolling 1 12-sided die and 1 8-sided die). The maximum and minimum rolls are 20 and 2, respectively, which is similar to rolling... | [
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17,
11,
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18,
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19,
11,
220,
20,
11
]
] |
<< Prev
Thanks to the PPCG community, Santa now has balanced his storage carts. Now, he needs to move them into the transport docks so that they can be sent to the loading bays. Unfortunately, the tracks to move the carts around are a mess, and he needs to figure out how to get them all around without them crashing tog... | [
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18,
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18,
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19,
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For another challenge I am writing, I need to verify that test cases are solveable with bounded integers. Specifically, I need to verify the following, for a non-empty array of integers A and an integer bit width n:
All integers a in A satisfy -2**(n-1) <= a < 2**(n-1) (representable with n-bit two's complement intege... | [
[
16,
11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20
]
] |
This challenge posed an algorithm for encoding an integer n as another integer r. What follows is a succinct explanation of that algorithm, using n=60 as an example.
The original algorithm
First, we encode the number as a string of brackets.
If n = 1, return an empty string.
Otherwise, we take n's prime decomposition... | [] |
The characteristic polynomial of a square matrix \$A\$ is defined as the polynomial \$p_A(x) = \det(Ix-A)\$ where \$I\$ is the identity matrix and \$\det\$ the determinant. Note that this definition always gives us a monic polynomial such that the solution is unique.
Your task for this challenge is to compute the coeff... | [] |
Unary numbers typically only represent nonnegative integers, but we can extend them to represent all integers as follows:
A positive integer N is represented as N 1's: 5 -> 11111
A negative integer -N is represented as a 0 followed by N 1's: -5 -> 011111
Zero is represented as 0
We can then represent a list of these ... | [] |
To check whether a list of non-negative integers is balanced, one can imagine putting respective weights on a board and then try to balance the board on a pivot such that the summarized relative weights left and right of the pivot are the same. The relative weight is given by multiplying the weight with its distance to... | [
[
16,
11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20
],
[
11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20,
11
]
] |
Definition
An arrowhead matrix is a matrix that has all entries equal to 0, except the ones on the main diagonal, top row and leftmost column. In other words, the matrix should look like this:
* * * * * *
* * 0 0 0 0
* 0 * 0 0 0
* 0 0 * 0 0
* 0 0 0 * 0
* 0 0 0 0 *
Where each * is any non-zero entry.
Task
Given a squa... | [] |
This has no practical purpose but it could be fun to golf.
Challenge
Given a number n,
Count the amount of each digit in n and add 1 to each count
Take the prime factorization of n
Count the amount of each digit in the prime factorization of n, without including duplicate primes
Create a new list by multiplying togeth... | [] |
Introduction
You have a friend that keeps asking you for loans and you are getting tired of it. Today, he came for a loan again. Instead of turning down his offer, you get a great idea: troll your friend by giving him as many coins/bills as possible.
Challenge
You will take as input: the amount of money your friend wa... | [] |
A doubly linked list is a data structure in which each node has a value as well as "links" to both the previous and next nodes in the list. For example, consider the following nodes with values 12, 99, and 37:
Here, the nodes with values 12 and 99 point to their respective next nodes, with values 99 and 37. The node w... | [
[
220,
16,
11,
220,
16,
11,
220,
17,
11,
220,
18,
11,
220
],
[
16,
11,
220,
16,
11,
220,
17,
11,
220,
18,
11,
220,
20
],
[
11,
220,
16,
11,
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17,
11,
220,
18,
11... |
Challenge
Given a non-negative integer, output whether it is possible for two dates (of the Gregorian calendar) differing by exactly that many years to share a day of the week. A year is assumed to be a leap year either if it is divisible by 4 but not by 100, or if it is divisible by 400.
Output may be:
falsey/truthy ... | [] |
It is well known that odd primes will appear in Pascal's triangle exactly twice. However, not all numbers that appear exactly twice in Pascal's triangle are prime. We'll call these numbers Pascal primes.
Pascal primes are composite numbers that appear exactly twice in Pascal's triangle. The first few Pascal primes are... | [
[
11,
220,
16,
17,
11,
220,
16,
19,
11,
220,
16,
21,
11
],
[
220,
16,
17,
11,
220,
16,
19,
11,
220,
16,
21,
11,
220
]
] |
Inspired by Taken from a question at Stack Overflow.
The challenge
Given an integer n>1, output all arrays that can be obtained by swapping exactly two entries in the array [1, 2, ..., n].
The arrays can be produced in any order.
You can consistently use [0, 1, ..., n-1] (0-based) instead of [1, 2, ..., n] (1-based).
A... | [] |
Challenge
Given a grid like this,
1 2 3 4 5 6 7 8
1 . . . . . . . .
2 . # . . . # . .
3 . . . . . . . .
4 . . . . . . . .
5 . . . . . . . .
6 . . # . . . . .
7 . . . . . . . .
8 . . . . . . . .
write a piece of code that can determine the size of the largest square that does not include a '#'. (The answer to this in... | [] |
The Task
Given an input positive integer n (from 1 to your language's limit, inclusively), return or output the maximum number of distinct positive integers that sum to n.
Test Cases
Let f define a valid function according to the task:
The sequence for f, starting at 1:
1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5... | [] |
Introduction:
At home we have a clock that strikes the stated amount at each hour, but also strikes once at every half-hour. So from 0:01 to and including 12:00 it strikes in this order:
1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 1, 10, 1, 11, 1, 12
Challenge:
Given an integer n, output a list of time-frame... | [] |
The Collatz conjecture postulates that if you take any positive integer, then repeat the following algorithm enough times:
if number is odd, then multiply by three and add one
if number is even, then divide by two
you'll eventually end up at 1. It seems to always work, but it's never been proven that it always does.
Y... | [] |
Ethereum is a blockchain platform. It has its own native cryptocurrency, ether, but in this challenge, we'll be focusing on its ability to run smart contracts.
The ERC-20 standard describes an implementation of fungible tokens within a smart contract. Some examples of this implementation are EOS, OmiseGo, and the Golem... | [] |
Given two positive integers A and B, return the position p that minimises the number of prime factors (counting multiplicities) of the resulting integer, when B is inserted in A at p.
For example, given A = 1234 and B = 32, these are the possible insertions (with p being 0-indexed) and the corresponding information abo... | [] |
Note: The title of this question should be "Loop It", but because title needs to be at least 15 characters, there are some invisible spaces. This note is such that the challenge can be searched for.
Challenge
Given a finite list of unique integral points in the plane, find a polygon whose vertices are exactly those... | [] |
A positive integer x is a square triangle number iff there are two different positive integers, y and z, which are smaller than x such that all of the sums
x + y
x + z
y + z
are perfect squares.
For example 30 is a square triangle number because
30 + 6 = 62
30 + 19 = 72
6 + 19 = 52
Your task is to write some code that... | [] |
Challenge
Write a program that takes an 11x11 array of integers, and constructs a 3D ASCII block building, where each value in the array represents the height of a column of blocks at the coordinates matching the array position. A negative height is a "floating" column - only the top block is visible.
Example
... | [] |
When multiplying monomials in the Milnor basis for the Steenrod algebra, part of the algorithm involves enumerating certain "allowable matrices".
Given two lists of nonnegative integers r1, ... ,rm and s1, ... ,sn, a matrix of nonnegative integers X
is allowable if
The sum of the jth column is less than or equal to... | [] |
Inspired by this Math.SE question.
Background
The Fibonacci Sequence (called F) is the sequence, starting 0, 1 such that each number (F(n)) (after the first two) is the sum of the two before it (F(n) = F(n-1) + F(n-2)).
A Fibonacci Sequence mod K (called M) is the sequence of the Fibonacci numbers mod K (M(n) = F(n) % ... | [
[
16,
11,
220,
16,
17,
11,
220,
16,
19,
11,
220,
16,
21
],
[
16,
11,
220,
17,
11,
220,
18,
11,
220,
19,
11,
220,
20
],
[
11,
220,
16,
17,
11,
220,
16,
19,
11,
220,
... |
Given a list of hole yardages, green sizes, a slice angle and a max distance, compute a golf score.
Assumptions
Earth is flat
All greens are circular
Slice angle will be between -45 and 45 degrees and will be given in degrees
All distances in the same metric (yards or meters, doesn't matter)
No out of bounds, obstruct... | [] |
Inspiration.
Given (by any means):
A two-argument (or single argument consisting of a two-element list) black box function, f: ℤ+ × ℤ+ → ℤ+ (input and output are 1, 2, 3,…)
A strictly positive integer matrix with at least two rows and two columns
return the matrix's function trace.
What is a function trace?
A normal ... | [] |
Challenge:
Input: Three integers: bottom-edge length; starting amount of grains of sand; index
Output: Output the state of the bottom part of an hourglass at the given index, based on the given bottom-edge length and amount of grains of sand.
Challenge rules:
We simulate the grains of sand with digits 1-9
We put the c... | [] |
Introduction
Output all the numbers in specific base that would appear in an adapted version of the game of seven.
Challenge
Your task is to output all the numbers in a given base in a given range, skipping the ones matching certain conditions.
You will be given four inputs: base elim start and end. The roles of the f... | [] |
Input is an r by c matrix of non-negative integers (you may input r and c as other parameters if this helps with golf). This may be inputted as a 2D array or, if you prefer, a 1D array (though taking in r this time is necessary). Strings separated by spaces to distinguish rows and newlines to distinguish columns are al... | [] |
Input:
A matrix containing integers in the range [0 - 9].
Challenge:
Determine if all non-zero elements are connected to each other vertically and/or horizontally.
Output:
A truthy value if all are connected, and a falsy value if there are non-zero elements/groups that aren't connected to other elements/groups.
Test ca... | [] |
This challenge is from an admission test to a closed number cyber security course. Anyway it doesn't have to do with cyber security, it's just to test the students logical and coding skills.
Task
Write a program that removes entries from an array so that the remaining values are sorted in a strictly decreasing order an... | [] |
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