Questions tagged [counting]
For challenges regarding counting the number of occurrences of some characteristic.
130 questions
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Count number of families of sets satisfying a list of criteria
CHALLENGE
This problem has a math background.
For n=1,2,3,4 we want to count the number of families of sets with maximum n elements that satisfy many criteria of the form:
$$\bigoplus_{k\in A,A\in \...
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Golomb's self-describing sequence problem [duplicate]
Inspired by this problem.
Golomb's self-describing sequence g(n) is a sequence where any natural number n is repeated within the sequence g(n) times.
Given an input of \$ n \$, output: $$ \left( \sum_{...
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Replace 0s In a String With Their Consecutive Counts
Challenge
Given a string of any length which contains only digits from 0 to 9, replace each consecutive run of the digit ...
user113990
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votes
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Counting overlapping objects
Consider a NxN pixel grid with up to M objects drawn on it, either squares or diamonds:
square
diamond
The objects may overlap, so recognition is hard. The task is to give the minimal possible ...
34
votes
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Converge to a number
Your challenge is to, given a positive integer n, count up to each digit of it, giving the effect of converging on it.
Basically, count up to the first digit of n by its place value (\$⌊\log_{10}\left(...
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Counting and so on
Content
You count numbers every day (I think), and most of you know how to count properly, the one next to 1 is 2, and the next ...
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Replace all items with their counts
Task:
Given an array of numbers as input (you can choose what subset, such as integers or natural numbers), replace all items with the number of times they appear within the array. As an example, <...
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Autogrammatic pairs
For today's task, we have two programs, P and Q, both in the same language. Each of them receives a single-character input.
If P receives character K, P says how many times K appeared in Q. (You can ...
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Eye test - How many squares are in this picture?
The picture:
Sick of the same old grid where the answer is simply a square pyramidal number?
Accept the challenge and write a program that given a positive integer \$n\$ counts how many squares are in ...
- 2,463
13
votes
6
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Number of solutions to a binary weight equation
We define \$a(n)\$ as the 1-indexed position of \$n\$ in the sequence of positive integers with the same binary weight, i.e. the same number of 1's in their binary representation. This is A263017.
...
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Acyclic orientations of an n-dimensional cube
The goal of this challenge is to check and extend the OEIS sequence A334248: Number of distinct acyclic orientations of the edges of an n-dimensional cube.
Take an n-dimensional cube (if n=1, this is ...
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How many spaces are there? [duplicate]
Your task is to input a string, and output the number of spaces in the string.
This is code-golf, so least number of bytes win. Your
Test Cases
Double quotes are not part of the test cases.
...
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3
votes
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answer
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Black and white shirt 2
This is a more complicated version of this puzzle. The premise is the same but a few rules differ in a few key places, making for a more complex problem.
Assume I have some number of black shirts and ...
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votes
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A scene of Jimmy diversity
As you probably know, there have been multiple lovely Jimmy challenges recently popping up. In these challenges, you were challenged with our beloved friend's acrobatics skills. Now we've got a ...
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How fast am I vrooooming?
Introduction
My car speedometer was hacked! Instead of showing me how fast i'm driving, it just shows: "Vroooom!" Please help me know how fast i'm going.
Challenge
Take a string as input, ...
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votes
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Recursively count lines of code, excluding empty lines and comments
Requirement: Write a program (in any language) that counts the number of lines of code in files matching *.sh in the directory tree starting from the directory that ...
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Saddle points in a matrix
A matrix can be thought of as the altitudes of a surface in 3D space.
Consider the 8 neighbours (orthogonal and diagonal) of a cell as a cyclic sequence in clockwise (or anticlockwise) order. Some ...
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Assign Airliner Seats
Inspired by last week's APL lesson.
Given an uppercase 2D seat map and a 1D list of customers, return the seat map and the customer list but modified as follows (to indicate occupied seats and seated ...
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Count the Matchsticks
Most people here are familiar with seven segment displays, which are also used in matchstick puzzles. Below are the digits 0 through ...
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Count edits accounting for grace period
When you edit a post on SE, any further edits within a 5-minute grace period are merged into it. Given a list of times you edit a post, count the edits not in a grace period.
Say you edit at minutes <...
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Sequence Without Sevens [duplicate]
This challenge is based on a drinking game. I advise against alcohol consumption while programming.
In this game, the players count up in turns: the first player says ...
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Number Lockers!
Given a positive integer < 100 (from 1 to 99, including 1 and 99), output that many lockers.
A locker is defined as the following:
...
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Count how many months are having a full 31 days by counting knuckles
How many of you that still use your own knuckle to determine whether a month is having a full 31 days or less?
You job is to write a program to count how many months, in a month range, are having a ...
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GET your dubs together
On 4chan, a popular game is get. Every post on the site gets a sequential post ID. Since you can't influence or determine them, people try to guess (at least a part of) their own post number, usually ...
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