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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What algorithm-family or problem-space description fits? Industrial process feeding ingredients to process

Our process continuously feeds (normally <= 8) ingredients from a choice of hundreds, using 3 feeders only. So if ingredient count X is > 3, 3 through X are stirred together in a batch process and ...
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10 views

Boundry traversal in binary tree

How to perform boundary traversal in binary tree using only single traversal of the tree? I am doing it in this way (not a single traversal): void printBoundary (struct node* root) { if (root) ...
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3answers
196 views

SQL - Algorithm for finding availability of a resource

I'm having trouble creating a mysql compatible algorithm for this. Background App with mysql, perl and JS. It's a booking system where each booking is comprised of a start, end and qty. Start and ...
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2answers
220 views

Traverse a matrix using a linear index to get an evenly distributed values sample

I'm looking for an algorithm idea on how to traverse a matrix using a linear index while avoiding row/column based traversals to get a more diverse distribution of values. To understand this better, ...
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1answer
22 views

Matrix distribution to process grid

I need to write a program, which will perform LU-decomposition, etc. The problem is that I don't know about the preferred way to distribute the loaded matrix from the root process to other processes. ...
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1answer
149 views

Solving a Sudoku variant with an unknown element

I recently stumbled upon a special Sudoku variant and am now struggling to effectively solve it programatically. Consider the following initial 6x6 grid: The rules The red question mark is ...
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15 views

Finding Contextual Nodes in a Knowledge Graph [migrated]

I'm currently participating in developing a knowledge graph that uses ConceptNet and a few others as its data sources. It uses the same architecture as ConceptNet namely it is stored as a hypergraph ...
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21 views

DIstribution of unique content [on hold]

I would like to distribute of unique content via web browsers. My task is have one part of content (part of movie, chapter in book, ... for example) only on one browser (end user). Another users can ...
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1answer
119 views

Algorithm to find minimal set

I have a set of sets S and I want to find a minimal set of elements M such that each set in S shares at least one element with M. S = set of sets ∀ f∈S ∃e · e∈f ∧ e∈M For example: S = {{1}, {1, 2, ...
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NullPointerException from tring to get seperate RGB components [migrated]

I am trying to get the seperate RGB components from each element in a 2D color array,but it keeps throwing a NullPointerException and I am not sure why. It might be something small that I missed, so ...
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10answers
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Is it reasonable to assume that any physical quantity can be represented by a 64-bit integer without overflow or underflow?

The original binary search algorithm in the JDK used 32-bit integers and had an overflow bug if (low + high) > INT_MAX ...
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PSO – how Dimensions are set up?

I am coding a Particle Swarm Optimization in C++. I have been for days trying to understand the theory of how dimensions work in each different problem. In the many examples I have seen, all of them ...
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48 views

Algorithm Space and Time Complexity with Consideration for I/O (eg cache)

Is there an expression of performance for an algorithm or data structure that attempts to consider cache and other hardware concerns? Context: in my class we're looking at binary trees and it seems ...
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54 views

Traversing game state space : more search leads to bad results [migrated]

I am cross posting this question from codereview as i found that it to be non-responsive. I am trying to solve a problem which i think is TSP on a 2-D grid. So, i am trying to get the best result ...
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1answer
183 views

Efficient algorithm for Virtual Machine(VM) Consolidation in Cloud

PROBLEM: We have N physical machines(PMs) each with ram Ri, cpu Ci and a set of currently scheduled VMs each with ram requirement ri and ci respectively Moving(Migrating) any VM from one PM to ...
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4answers
525 views

Need help identifying a league scheduling algorithm

I am trying to create a sports league scheduler. I am having trouble identifying an algorithm to help me efficiently fill in each slot. Sample data to build the schedule would be: 10 teams Each ...
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8answers
10k views

What methods are there to avoid a stack overflow in a recursive algorithm?

Question What are the possible ways to solve a stack overflow caused by an recursive algorithm? Example I'm trying to solve Project Euler problem 14 and decided to try it with a recursive ...
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1answer
57 views

timed events to modulation of real-time audio

I am new very to audio programming and am having trouble figuring out the right kind of algorithm for converting control events (e.g. like MIDI) to real-time sound genesis with a buffer. At the ...
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51 views

Connected components of undirected graph

Suppose I have an undirected graph G with vertices v1...vn and edges. Right now it is in adjacency list representation. For every time moment I have as input some subset of vertices that are "active" ...
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Is this a good algorithm? [on hold]

First off let me say, I have never asked a question on programmer.se before, so I don't know if this is the kind of question you guys want on this site. I was going to put this on code-review, but I ...
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2answers
87 views

MJRTY - A Fast Majority Vote Algorithm isn't work [on hold]

The MJRTY algorithm sets out to solve the problem of finding the majority element in a stream (an element comprising more than 50% of the stream). Moore proposed to solve this by using only 2 pieces ...
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Rectangle bin packing: multiple containers [on hold]

I have the following problem (non-academic): Pack several rectangles, which have random dimension, within rectangles that have a known and fixed dimension. Properties: - You will need to use ...
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3answers
241 views

Abstraction in algorithms

I asked some questions about algorithms, and some replied they are abstract concepts, however I don't know what abstraction means for algorithms or how it applies. For objects, I know if we remove ...
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51 views

A fast algorithm for a simple multi-objective minimization?

I have a set of n (arbitrary) integer numbers S which I want to partition into k subsets S_i each of size n/k (you can assume that k divides n). Let A be the arithmetic mean of elements of the set S. ...
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1answer
52 views

Should changes to FNV-1A's input exhibit the avalanche effect?

This is kind of related to Which hashing algorithm is best for uniqueness and speed?. In that question, the excellently written top answer notes, Randomnessification The other subjective ...
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113 views

Would adding more digits be a way to scale a order generation service? [closed]

I am working on interview questions from Amazon.com Software Development Engineer Intern Interview Questions. One of the interviewees was asked "give a scalable system design of Amazon.com's order ...
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9answers
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Why is it impossible to produce truly random numbers?

I was trying to solve a hobby problem that required generating a million random numbers. But I quickly realized, it is becoming difficult to make them unique. I picked up Algorithm Design Manual to ...
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2answers
128 views

How to iterate through all permutations of valid links between nodes

Imagine a 2D area, with a number (array) of nodes (or points) defined within it, in arbitrary (but known) positions (integer x,y coordinates), like this: From there I want to be able to, ...
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128 views

c++11 random: why different range of int and real?

In the c++11, we now have <random> to produce random number. About uniform distributions, we have following int_distribution and double_distribution: uniform_int_distribution-produces integer ...
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111 views

What is a formal definition for an algorithm step?

Consider the following code to find the K th minimum element of an array: FindKthMin(A[], k) { A = Sort(A); return A[k]; } Could it be an algorithm without specifying the sort details? ...
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151 views

What benefit is there to using recursive binary search over iterative binary search or vice versa?

In a recent assignment for my programming 2 class we tested the efficiency of searches by populating a java ArrayList with 13,040 strings. The sequential search was obviously slower than the binary ...
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25 views

Finding the largest bundle of flagged points

I am currently working to develop a program that takes in an array of 4 columns and around 200,000 rows. Each column represents x, y, z (coordinates), and a flag denoting whether or not this point is ...
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2answers
161 views

Number of strings containing a specific substring

I've seen numerous questions (and answers) concerning the number of binary strings (e.g "10010" containing some binary substring (e.g "00"). I'd like to know if there is a way to generalize this: ...
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219 views

Is recursion a declarative approach to solve the problems?

I have noticed many problems in algorithms textbook are solved by recursion (divide and conquer, backtracking,...) As I tried to enhance my skills in writing them, I have noticed, I just need to ...
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What is the most efficient / fastest way to keep a list in order?

I implemented Dijkstra's path finding algorithm in JavaScript and a big part of it involves storing the distances to nodes and fetching the smallest. The distances change often and the smallest is ...
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Do algorithms depend on computer architectures?

I read somewhere (forgot which book it is) that algorithms are independent of computer architectures. Some even say algorithms are themselves computation (machines?)? On the other hand, books on ...
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43 views

Approaches to get stats like average latency in last N seconds

I am receiving messages with latency information (LI, {date, latency}). For statistical reasons: (I am open to approx. approaches, stats monitor will be updated in 6-60 seconds) I want to monitor ...
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3answers
163 views

number of strings, when each character must occur even times

I've been bashing my skull at this problem for some time now, and its really starting to frustrate me. The problem is: I have a set of characters, A, B, C, and D. I have to tell in how many ways a ...
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1answer
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faster algorithm for finding all subsets

This is the algorithm (pseudocode) I have right now for finding all subsets for a given set with length k: void allSubsets(set[]) { for (i = 0; i<k; i++) { for (j = i + 1; j<k; j++) ...
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122 views

Why is the “period of a (pseudo)random number generator” important?

I've been trying to understand (pseudo)random number generator code from various sources and the concept of the period continues to elude me. To satisfy the minimum level of understanding, I've tried ...
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70 views

Algorithm for a fast search

I am looking for an algorithm (pseudocode, R code) for my problem here. This looks like a lot to read but is actually very very easy to read, and I am just trying to be verbose. I have a list (say ...
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3answers
255 views

“Read user input”: Could it be a step of an algorithm?

Based on this definition of algorithm from Wikipedia: In mathematics and computer science, an algorithm is a self-contained step-by-step set of operations to be performed. Algorithms exist that ...
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2answers
254 views

How are the tiles in WORDAMENT organized?

I'm trying to create a word game, just like WORDAMENT, in my spare time. In order to present a new round, I need to create a board with 16 letters organized in a 4*4 grid. Currently, I'm generating ...
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42 views

Measure and locate areas of similar value in an image

I saw this picture online and wanted to see if I could create an algorithm to give ordinary images an effect like this: http://justinlivi.net/wp-content/uploads/2011/01/Living_In_Digital.jpg My idea ...
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1answer
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worst case comparisons for special case insertion sort [closed]

Consider an Insertion Sort with a Sentinel on n values, where every value occurs exactly twice in the input (so n must be even). So the best case input for comparisons is when the elements are ...
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46 views

How to measure the quality of a web crawler algorithm [on hold]

I developed a new web crawler algorithm as a part of my thesis using java. Now i should compare my work with previous developed crawler algorithms. Since every developed algorithm has its own web ...
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249 views

C# if statements

I am currently working on a C# checkers game for a university project in programming. But i have came to the point where i need to check whether a piece can be moved, or jump, but i feel like i'm ...
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Relation between object orientation and algorithms

As I read some algorithms textbooks, they are full of clever procedures for some problems (sorting, shortest path) or some general methods (recursive algorithms, divide and conquer, dynamic ...
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What is determinism in computer science? [migrated]

I was asked if my computer program (in Java) was deterministic. I'm wondering how could it be not? There is no such thing as a non-deterministic Java program right? Even if I use a random number ...
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Dynamic Programming Problem - To find smallest integer number 'x' which contains only digits 1's and 0's such that x mod n = 0

To design an algorithm that will output the smallest integer number 'x' which contains only digits 1's and 0's such that x mod n = 0 and x > 0..... For example: 2 divides 10 3 divides 111 4 ...