In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning.

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Is studying algorithms important for game development? [closed]

I am fairly new in the programming world, I have a 1-year experience and I learned by watching online courses, and I made few iOS apps. Now I am moving into game development and I already ...
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2answers
100 views

MaxHeap-like data structure supporting max AND min, also decrease-key (yes decrease-key)

For the purpose of implementing an optimization algorithm (finding the minimum of a multivariate function) I want to create a data structure that supports the following operations: load from array ...
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3answers
69 views

Algorithm to generate parallel path inside polygon

A path is defined as a list of 2D points (x,y) (and may be open or closed). Given a path p, what is an algorithm which generates a path p' which is "inside" p and at constant offset to p i.e. each ...
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1answer
88 views

Pairing 40 people over 20 days such that no pair is the same twice or more [duplicate]

I'm trying to figure out what algorithm / method I can use to figure out how to pair people together such that the pairs aren't repeated i.e. if a unique individual is denoted by Px where x is their ...
2
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3answers
225 views

Close to knapsack problem?

I think that I am trying to solve a problem somewhat similar to a knapsack problem. I am not sure though. Please see the input given below and my solution. There are three types of items and 4 ...
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0answers
100 views

Smallest number of rectangles covering marked parts of grid

I have an N by N grid of cells, and certain blocks are marked: +--+---+---+---+ | | | | | | | x | x | | | | x | x | | | | | | | | | | | x | +--+---+---+---+ I would like to ...
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1answer
138 views

Increment or double problem

I have a problem with an assignment. In this assignment I have to create a program which needs to calculate how many different possibilities are there to get from number a to b. To get from a to b you ...
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0answers
63 views

Combining items from several lists with pagination

I am trying to come up with an algorithm for getting items for a news feed from several sources. There are multiple lists of data: S1, S2, ... Sn. Each of these lists has a certain known amount of ...
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1answer
89 views

Split multiple overlapping intervals to non overlapping intervals

currently I try to build an algorithm to split an array of overlapping intervals to a new array with non overlapping intervals. For example: Array of overlapping intervals: [ {0,7}, {8,12}, ...
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4answers
227 views

List comparing techniques for faster performance

I need to cross names from two lists, and find all occurrences of one name in the other. The lists are too big, one have 50k elements and the other 400k. For a small list I would use two foreach ...
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1answer
73 views

Translation algorithm - combinations to indices

I have a deck of 52 poker cards represented as array of int - [0, 1, ... 51]. There are 2.598.960 possible combinations of 5 cards. I can generate all combinations like this: #id #combination ...
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62 views

scrabble solving with maximum score

I was asked a question You are given a list of characters, a score associated with each character and a dictionary of valid words ( say normal English dictionary ). you have to form a word ...
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5answers
543 views

Fastest way to determine if a value is in a list?

I'm aware there may not be a good solution to this problem. I'm looking for a fast algorithm that determines whether or not a value (let's say an integer) exists in a set of values, however I need the ...
2
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3answers
221 views

fast, say O(log2(N)), sliding median algorithm

So I know how to do a fast O(log2(N)) sliding max or sliding min algorithm. Brookes: "Algorithms for Max and Min Filters with Improved Worst-Case Performance" IEEE TRANSACTIONS ON CIRCUITS AND ...
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1answer
262 views

Calculate Big-O for nested for loops

I found this nested loop to calculate the Big-O notation. for(i=0;i<n;i++) for(j=0;j<i*i;j++) for(k=0;k<j;k++) I got the time complexity for the algorithm with this polynomial ...
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0answers
15 views

Polling more recent / active items more frequently

I'm setting up a service that is meant to query, via a rate-limited API, a number of posts in real-time. Now, some of these posts can be several months old, and they should really only be queried, ...
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2answers
148 views

Is there a approximate string comparison function which is odd like mathematical functions are odd?

I say odd like a mathematical function, a mathematical function is odd if f(-x) = -f(x) I understand that comparing two strings may seem to have little to do with this, because the arguments cannot ...
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0answers
70 views

Compare names and the use of Levenshtein's algorithm

I need to cross names from two lists. What is the best away to compare the names? As you may expect, in one list we can have the complete name, on the other just the first and last. Besides that, ...
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3answers
165 views

Does it really need to convert decimal,string, etc to binary?

I'm very new to programming. Just read some articles about algorithm for converting a decimal or string to binary. But,according to what I know, computers hold these data in binary form. So why don't ...
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1answer
107 views

How to count sort comparison

When it is said that this sort has M number of comparisons what does it mean? As an example: procedure bubbleSort( A : list of sortable items ) n = length(A) repeat swapped = false ...
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2answers
128 views

Average number of comparison for sort algorithms

I need to write different sort algorithms such as bubbleSort insertionSort selectionSort quickSort mergeSort And measure how many average comparison does each one for N number (averaging between ...
2
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0answers
98 views

Asking questions to the user based on results of previous questions

I have to select a question that would help me make me sure the user knows about a given subject. As an example, let's assume the user hasn't answered any question yet. Every question has a scope ...
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9answers
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Big O Question about an algorithm with (n^2 + n) / 2 growth rate

I'm asking this question because I am confused about one aspect regarding big O notation. I am using the book, Data Structures and Abstractions with Java by Frank Carrano. In the chapter on the ...
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1answer
66 views

Pathfinding in a 3d world with obstacles?

What are some methods for pathfinding in a 3d world? Object X needs to move from Point A to Point B but it might have to avoid things like asteroids, planets or gas pockets that makes the object ...
3
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1answer
73 views

Consistent snapshot

Suppose process A has a consitent snapshot of some entities. And it is constantly receiving updates for this enteties. Now client B connecting to A and it should receive the consistent snapshot of ...
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0answers
43 views

Can't figure out how to parallelize the calculation of the amount of offspring expected for species in genetic algorithm

I developed a genetic algorithm in java 8 taking advantage of its reasonably free parallelism opportunities with Streams. As you are likely aware, running the epochs takes its time for even a test ...
2
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1answer
141 views

Finding the closest n points to any arbitrary point in two dimensions (r-tree, quadtree, spatial index)

I have a distribution of two dimensional point objects. How is it possible to find the nearest N number of points to any given point without iterating over the entire collection of points (and only ...
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1answer
189 views

General Way to convert a loop (while/for) to recursion or from a recursion to a loop?

This problem is mainly focusing on the algorithm, maybe something abstract and more acedemic;) The example is offering a thought, I wanna a generic way, so example is only used as to make us more ...
12
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2answers
466 views

Ant colony algorithm

I am a student working on an ant colony simulator for a course project. The algorithm for it is (obviously) an ant colony algorithm. I know there are various forms of the algorithm but all of those ...
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0answers
34 views

build list of possible permutations with dynamic set size

I'm trying to develop code/pseudocode to build a list of all permutations given the following data. I'm developing in a java-like language for a web app. I don't have any java libraries for this ...
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1answer
59 views

Using Euclidan Distance to intialize centroid of K-Means

I need to initialize centroid of K-Means using Euclidan distance. Is it possible? If so how the algorithm should be? I have been stuck for a while and couldn't figure it out. Thanks for your time.
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1answer
99 views

Sorting Sentences by New Words in Each

A very useful learning tool I stumbled across for Chinese was a massive list of sentences that, barring the first 10 or 15, only differed by the ones before by one or two words, or at least as few as ...
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1answer
255 views

Turn over cards in minimum number of steps

Imagine you're given an array of cards. Some of them are facing down (0), while some of them are facing up (1). Is it possible for given fixed K to turn all the cards face-up by turning over any K ...
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1answer
45 views

Render order of two-edge directed node graphs

I'm trying to find an algorithm for graphs with the following contents: Nodes with no edges leading out of them (shown here as a red circle) All other nodes have exactly two edges leading out ...
2
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1answer
51 views

equal distribution within given set of users

I have a requirement where I have a list of entity and users who that entity can be assigned E1 can be distributed by U1 or U2 E2 must be distributed by U5 E3 can be distributed by U2 ...
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1answer
155 views

Creating algorithms [closed]

I am a relatively new programmer. I can pick up languages and learn syntax at a speed that I consider good, but I can't figure out how to solve problems logically using algorithms very well. I know ...
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3answers
270 views

Check distance between all elements in a list of numbers in O(n*lg(n))

I have an exercise for my algorithms and data structures class, where I basically have to implement a divide and conquer algorithm or function called check_distance to determine whether all numbers in ...
4
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1answer
113 views

Image segmentation - show or hide clusters

I'm trying to make a small program in c#, that will downsample image to specified amount of colors (using K-means). Then, user will be able to hide\show colored areas(clusters) in image. I've ...
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0answers
65 views

How to search for patterns on a (game)board?

Assume a gameboard with two kinds of pieces. Let the task be to find a common patterns of pieces, namely the patterns that lead to winning. The problem is general, but the game in question is ...
1
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1answer
132 views

Non-fixed-size Fenwick Tree implementation

I'm planning to implement a non-fixed-size Fenwick tree. That is, a Fenwick tree that allows interleaving range queries with adding/removing elements. All implementations and samples I've seen so far ...
2
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1answer
210 views

When designing a data structure, should I implement very inefficient operations for convenience?

(I've added the .NET tags because the data structures are for .NET, and this question should be considered in the context of the conventions for that platform.) I'm writing a library of immutable and ...
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2answers
100 views

Add file paths to database

I am scanning a directory of files and want to add them to a database. I have two variants: for file in walk(basedir): files.append(file) for file in files: add_to_database(file) versus ...
4
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3answers
159 views

Algorithm that generates a group of men and women who are each interested in everyone from the other gender

In my dating app, I need to compile lists of men and women where all of the men in the list are potentially interested in all of the women in the list, and vice versa. That is, in a list of 10 men ...
3
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2answers
252 views

How to draw rectangles for 2D arrays

I have an 2D boolean array that looks like this: [0][0][0][0][0][0][0][0][0][0] [0][0][0][0][0][0][0][0][0][0] [0][0][0][0][0][0][0][0][0][0] [0][0][0][1][1][1][0][0][0][0] ...
3
votes
3answers
516 views

How to model state of leaving/entering home

I have two sensors: One detecting if the door is open or closed, another if movement has been detected in the corridor. I want to detect if the person has left or entered home. Usually the person has ...
1
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1answer
127 views

What algorithm can be used to determine order given incomplete information?

Given a series of statements such as: a<c a<b b<c (Read as "a is before b", "a is before c", etc.) What is the order of the elements? In this example, the answer is a<b<c. A less ...
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2answers
149 views

Efficient datastructure to create size-limited dictionary

I need a class that acts like a dictionary but will constrain the total number of key/value pairs it contains. For instance, let's say the maximum number of entries is 1000 and the class already ...
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1answer
98 views

Find the best shuffle

I am trying to solve the following problem: Question Description: Given four integer numbers A, B, C, and D, a shuffle of them is a zero-index array, which consists of these four numbers in some ...
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1answer
122 views

How to create good positive and negative images for opencv to distinguish smiling from not smiling? [closed]

My goal is to create an opencv haar classifier xml that distinguishes between me smiling and not smiling. I created images, cut them, showing me smiling and as negatives not smiling. About 5000 ...
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0answers
86 views

Algorithm for the Simplication and Evaluation of Equations

As a new programmer messing around in python, I've been playing about with writing small programs which can calculate some of the stuff I did in maths at school. I've been trying to think of a way ...