0
votes
1answer
62 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 ...
-1
votes
0answers
37 views

Help finding the tilde of the following algorithm [closed]

Suppose I have an algorithm that takes N^100/2^N to complete. Would the tilde of this be 0? But then that does not make sense. However, since the alogrithm tends to 0 as N increases, what should the ...
0
votes
0answers
58 views

Estimating the time it takes for this quick find algorithm to complete [closed]

I am trying to run an estimate on how long this quick find algorithm takes on Union Find type problems. Here is the code: public int find(int p) { return id[p]; } public void union(int p, int q) ...
1
vote
2answers
158 views

How to measure algorithm accuracy?

I have a few optimization algorithms (for finding function minimum) and I'd like to check how good they are. Suppose I build test cases and compare the actual results to theoretical ones. What ...
0
votes
0answers
51 views

Approach for packing 2D shapes while minimizing total enclosing area

Not sure on my tags for this question, but in short .... I need to solve a problem of packing industrial parts into crates while minimizing total containing area. These parts are motors, or pumps, ...
0
votes
2answers
108 views

How to avoid or minimise use of check/conditional statement in my scenario?

I have scenario, where I got stream and I need to check for some value. If I got any new value I have to store it in any of data structure. It seems very easy, I can place conditional statement ...
2
votes
1answer
114 views

Asymptotic running time of for-loops

I have this question which I need answered: What is the asymptotic running time for the following piece of code? if (N < 1000) for (int i = 0; i < N; i++) for (int j = 0; j < N; ...
1
vote
1answer
75 views

Confusion in understanding the theorem on Amortization

I was reading a book on Algorithm Analysis by Micheal T Goodrich. I came across amortization technique and I got struck in understanding the proof of theorem. I am putting the theorem and the proof ...
0
votes
0answers
94 views

GSP Algorithm explanation

I've been trying to implement the GSC algorithm in C++, however I need help with clarifying the definition: http://en.wikipedia.org/wiki/GSP_Algorithm GSP Algorithm makes multiple database ...
0
votes
0answers
83 views

Algorithm / working approach to get a random list of data

I am working on a android schedule app but that isn't matter , the problem is a algorithm / methodology so you are welcome to just write the pusedo code to answer. The data is like this Place ...
1
vote
2answers
204 views

Given two sorted array in ascending order with same length N, calculate the Kth min a[i]+b[j]. Time complexity O(N)

Given two sorted array in ascending order with same length N, calculate the Kth min a[i]+b[j]. Time complexity O(N). Another variant of the question goes like this: given a matrix with sorted rows, ...
0
votes
0answers
30 views

Readers Writers algorithm help - starvation and no starvation

I found this link, as an explanation of r/w problem - http://pages.cs.wisc.edu/~bart/537/lecturenotes/s7.html But, I'm having problems realizing is there any starvation present here and why? Also, if ...
0
votes
1answer
201 views

How to develop an algorithm for brute-forcing / backtracking?

As a beginner programmer, I don't know how to conceptually think about brute-forcing. My mind can't really fathom how to write code that will try every possibility. I have a problem that I want to ...
0
votes
0answers
144 views

what is the meaning of f(n) = O(g(n))? [duplicate]

I am reading 'Algorithm design manual' book by Steven S. Skiena. I would like to know what is f(n) and g(n)? I am a programmer and wanted to gain more knowledge about algorithms but now I am confused ...
1
vote
4answers
228 views

How to trace logical errors in algorithms [closed]

I am beginner in algorithms. Last year I participated in Google Code Jam. One of the major issues I faced during the competition was my code was working fine on my test cases, but when I submitted on ...
6
votes
3answers
2k views

Why Big Data Needs To Be Functional?

I started working on a new project lately related to Big Data for my internship. My managers recommended to start learning functional programming (They highly recommended Scala). I had a humbled ...
1
vote
1answer
122 views

How to calculate the worst-case runtime of this search-algorithm

I've written a special indexOf function for a list of unsorted unique values. I can search for one or multiple (unsorted) values, passed as array/list, and the function will return me an array/list ...
5
votes
2answers
562 views

difference between accounting and potential methods in Amortized Analysis

I was going through the Introduction to Algorithms by Cormen et al.In the chapter titled Amortized Analysis,the difference between accounting and potential methods is given like this The ...
5
votes
1answer
197 views

Bin sorting problem - Please help categorize

I have a problem I am developing a solution for and currently I solve it with a brute force solution that checks all possibilities. It works for small numbers of bins but I'd like to work with a ...
6
votes
6answers
4k views

Why is binary search,which needs sorted data, considered better than linear search?

I have always heard that linear search is a naive approach and binary search is better than it in performance due to better asymptotic complexity. But I never understood why is it better than linear ...
2
votes
1answer
192 views

Algorithm in undirected BFS graph

I'm trying to put together an algorithm that will display the node degree for every node in a breadth first tree graph (assume BFS was called). Assume it's an undirected graph. I'm not sure how to ...
1
vote
1answer
817 views

Matrix Pattern Recognition Algorithm for a 2D space

I have a picture that I elaborate with my program to obtain a list of coordinates. There is a matrix represented in the image. In an ideal test I would get only the sixteen central points of each ...
5
votes
4answers
462 views

Find the peak of each islands in sparse matrix

I have a sparse matrix that contains several islands of unknown size. I would like to find the highest peak of each islands. Consider this matrix as an example: 0 0 1 0 0 0 0 0 0 1 2 1 0 0 0 0 0 3 2 ...
0
votes
1answer
345 views

Priority queue for Kruskal's algorithm with running time O(E lg V)

I'm reviewing my notes on Kruskal's algorithm and have a question about getting the runtime down to O(E lg V). By using a PQ with edges and a boolean array of which vertices we have added to our tree ...
26
votes
5answers
3k views

Divide and Conquer algorithms – Why not split in more parts than two?

In divide and conquer algorithms such as quicksort and mergesort, the input is usually (at least in introductory texts) split in two, and the two smaller data sets are then dealt with recursively. It ...
2
votes
4answers
340 views

Approach to simplifying an algorithm

For completely random reasons*, I wrote some code that calculates and displays the following expression: P=1*(2+2)(3+3+3)(4+4+4+4)..(n+n...… Which is equivalent to (n!)^2 The version I wrote ...
4
votes
8answers
888 views

How meaningful is the Big-O time complexity of an algorithm?

Programmers often talk about the time complexity of an algorithm, e.g. O(log n) or O(n^2). Time complexity classifications are made as the input size goes to infinity, but ironically infinite input ...
8
votes
1answer
639 views

Possible Damerau-Levenshtein improvement?

I recently implemented the Damerau-Levenshtein distance algorithm from the pseudocode on Wikipedia. I couldn't find any explanation of exactly how it works and the pseudocode uses completely ...
5
votes
5answers
673 views

Why interviewers want Optimal Algorithms

In an interview with a software company they asked me some algorithm design questions. Being strong in mathematics I was able to solve it mathematically, but each time when I propose my algorithm ...
3
votes
1answer
738 views

A* Algorithm Completeness Proof

The A* Algorithm is the optimal (provided the heuristic function is underestimated), complete & admissible (provided some conditions). I know the proofs of admissibility & optimality. But how ...
2
votes
1answer
201 views

How to compute amoritized cost for a dynamic array?

I am trying to understand how to do the amortized cost for a dynamic table. Suppose we are using the accounting method. Let A of size m be an array of n elements. When n = m, then we create a new ...
2
votes
1answer
171 views

How much times command executed? Looking for mistake

I have following piece of code: int sum = 0; for (int i = 1; i <= N; i++) for (int j = 1; j <= N; j++) for (int k = 1; k <= N; k = k*2) for (int h = 1; h <= k; ...
2
votes
1answer
368 views

Sublinear Extra Space MergeSort

I am reviewing basic algorithms from a book called Algorithms by Robert Sedgewick, and I came across a problem in MergeSort that I am, sad to say, having difficulty solving. The problem is below: ...
0
votes
1answer
177 views

Help with algorithmic complexity in custom merge sort implementation

I've got an implementation of the merge sort in C++ using a custom doubly linked list. I'm coming up with a big O complexity of n^2, based on the merge_sort() > slice operation. But, from what I've ...
1
vote
1answer
389 views

How should I compress a file with multiple bytes that are the same with Huffman coding?

On my great quest for compressing/decompressing files with a Java implementation of Huffman coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment, I am now at the point of ...
2
votes
4answers
759 views

How to discriminate from two nodes with identical frequencies in a Huffman's tree?

Still on my quest to compress/decompress files with a Java implementation of Huffman's coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment. From the Wikipedia page, I quote: ...
1
vote
1answer
176 views

Does it matter the direction of a Huffman's tree child node?

So, I'm on my quest about creating a Java implementation of Huffman's algorithm for compressing/decompressing files (as you might know, ever since Why create a Huffman tree per character instead of a ...
2
votes
1answer
323 views

Why create a Huffman tree per character instead of a Node?

For a school assignment we're supposed to make a Java implementation of a compressor/decompresser using Huffman's algorithm. I've been reading a bit about it, specially this C++ tutorial: ...