ALGORITHM QUESTIONS

Puzzle: Find largest rectangle (maximal rectangle problem)

this will help @lassevkI found the referenced article, from DDJ: The Maximal Rectangle Problem

Date : January 24 2021, 02:01 AM , By : FriendL

seems to work fine The interesting thing here is how you can do it in the least amount of drops possible. Going to the 50th floor and dropping the first would be disastrous if the breaking floor is the 49th, resulting in us having to do 50 drops. We

TAG : algorithm

Date : January 23 2021, 02:43 AM , By : Ashaea

Graph serialization

it fixes the issue Topological Sort (From Wikipedia):

TAG : algorithm

Date : January 22 2021, 04:45 PM , By : user119985

Peak detection of measured signal

Hope this helps You could try signal averaging, i.e. for each point, average the value with the surrounding 3 or more points. If the noise blips are huge, then even this may not help.I realise that this was language agnostic, but guessing that you ar

TAG : algorithm

Date : January 22 2021, 02:12 PM , By : pdkent

Big O, how do you calculate/approximate it?

it helps some times I'll do my best to explain it here on simple terms, but be warned that this topic takes my students a couple of months to finally grasp. You can find more information on the Chapter 2 of the Data Structures and Algorithms in Java

TAG : algorithm

Date : January 22 2021, 02:12 PM , By : user183275

What problems can be solved, or tackled more easily, using graphs and trees?

To fix the issue you can do The first thing I think about when I read this question is: what types of things use graphs/trees? and then I think backwards to how I could use them.For example, take two common uses of a tree:

TAG : algorithm

Date : January 22 2021, 02:12 PM , By : Tonix

Count the total number ways to reach the nth stair using step 1, 2 or 3 but the step 3 can be taken only once

I hope this helps you . Let res0[n] be the number of ways to reach n steps without using a 3-step, and let res1[n] be the number of ways to reach n steps after having used a 3-step.res0[i] and res1[i] are easily calculated from the previous values, i

TAG : algorithm

Date : January 12 2021, 07:00 PM , By : user109127

Algorithm for web crawler in Scala

it should still fix some issue You've explicitly set the return type to Any. Update it to be List[String] Reduce the scope of your exception handling to only include the code which may throw an exception. Using a for comprehension should facilitate t

TAG : algorithm

Date : January 12 2021, 08:33 AM , By : Anonymous

Maximum profit earned in Interval

help you fix your problem Assuming you have only one car, then the problem we are solving in Weighted Interval SchedulingLet us assume we have intervals I0 , I1, I2, ....In-1 and Interval Ii is (si,ti,pi)

TAG : algorithm

Date : January 11 2021, 05:14 PM , By : lonehunter01

Subset sum variation: find the subset that sums to >= target, with minimum overshoot

help you fix your problem This is a rather simple extension of the original program: we simply use the dynamic programming algorithm, but also store lists we generate if these are overshooting the original value.We can for example implement such algo

TAG : algorithm

Date : January 10 2021, 02:06 PM , By : Stephen Dewar

Algorithm to generate a segment maze

Does that help create a random path between point A and B randomly add walls as long as it doesn't lie on the path until you're satisfied

TAG : algorithm

Date : January 10 2021, 01:57 PM , By : pad

What is the typical method to separate connected letters in a word using OCR

wish help you to fix your issue The standard term for this process is "character segmentation" - segmentation is the image processing term for breaking images into grouped areas for recognition. "Arabic character segmentation" throws up a lot of hits

TAG : algorithm

Date : January 10 2021, 01:57 PM , By : ranja

Algorithms for finding closest vector

I think the issue was by ths following , use the cosinus similarity (http://en.wikipedia.org/wiki/Cosine_similarity) among the vectors and then sort them.

TAG : algorithm

Date : January 10 2021, 01:49 PM , By : Heals1ic

Rectangles Covering

should help you out Here's a divide and conquer algorithm. AVERAGE case complexity is very good and I'd say it's something like O(n log MaxCoords). Worst case could be quadratic though, however I think such a test would be pretty difficult to create.

TAG : algorithm

Date : January 10 2021, 01:47 PM , By : oiyto

Algorithm for performing decentralized search in social networks

should help you out From the paper "Searching For Expertise in Social Networks: A Simulation of Potential Strategies":Breadth First Search (BFS) broadcasts a query to all of one’s neighbors instead of picking a neighbor according to a heuristic. It c

TAG : algorithm

Date : January 10 2021, 01:47 PM , By : Nate Bedortha

Algorithm to find lenth of longest sequence of blanks in a given string

it should still fix some issue You won't be able to find a solution which is a smaller complexity than O(n) because you need to pass through every character in the worst case with an input string that has at most 0 or 1 consecutive whitespace, or is

TAG : algorithm

Date : January 10 2021, 01:45 PM , By : David Marchant

What is a data structure suited for representing railways with turnouts?

wish helps you You can represent the turnout as 2 vertices - one for each state of the turnout. So if you have source A and destinations B and C and turnout which can switch between B and C - you will have 2 vertices for this turnout: TB and TC. Also

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Schmidt

How to calculate angle of rotation of a rectangle, given its 4 points

may help you . I believe the angle alpha (marked green in the image) is what you are looking for. Assuming the lowest point of the rectangle is O(0, 0), this angle can be easily calculated as cos-1(a/sqrt(a^2+b^2)), where B(a,b) is the point with low

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : paolodm

What does the extra 0 added to the LSB in Modified Booth Algorithm do?

Does that help Assume we have to multiply A×B, where B=(bn-1 ... b1 b0)Booth, in its standard or modified version, works by rewriting terms bi.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Steve O.

What algorithm theory would I use for searching one full record in one big file which contains 100 millions records?

I hope this helps . If I were asked this question, I would start by asking questions to find out more about the problem domain. Some starting questions: Are the records in any particular order? Are the records all the same length, or variable length?

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : micaleel

Finding second largest element in sliding window

it helps some times There are many ways that you can solve this problem. Here are a couple of options. In what follows, I'm going to let n denote the number of elements in the input array and w be the window size.Option 1: A simple, O(n log w)-time a

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Mihai Mocanu

Algorithm to find the points closest to a given set of 3D lines

Does that help It's unclear how you want to cluster lines. By what criterion?You can certainly build a pairwise distance matrix and run almost any clustering algorithm (e.g., HAC, PAM, DBSCAN). The question then is what distance to use (minimum dista

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : cthulhup

Special Perfect Maze Generation Algorithm

this one helps. It looks like it's actually quite reasonable to generate mazes meeting your criteria using a two-step process:

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Terrence Poon

How do I calculate mathematically this algorithm's time complexity?

To fix this issue This is a recursive function. When m > n then it call this function again with parameter (m-n, n). So in worst case, suppose when m = 100, n = 1 then the value of parameter in every steps are -

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Brianna

How to do unspecific number of nested loop using only loops

I hope this helps you . Let's say I have a function that implement looping and recursion: , General scheme:

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Mighty Mac

Write method about 15-5-3 division rule

it fixes the issue The rule works. We say that 15 divides a number n if there is an integer q such that

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user177837

minimum number of operations to make two numbers equal

To fix this issue As mentioned in other answers, this can be approached using BFS in a graph whose nodes correspond to numbers and whose edges correspond to operations.Interestingly, sometimes, optimal paths need to contain quite large numbers (large

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user161314

How do I keep track of the shortest paths in the Dijkstra algorithm when using a min-priority queue?

Hope this helps You don't have to keep track of the whole path for each vertex as you've suggested. To produce the s-v paths themselves, the only thing you have to record for each vertex v is the edge that "discovered" it.In other words, as a vertex

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user170635

Buy Sell Stock with Transaction Fee?

will be helpful for those in need Your solution has a quadratic complexity and results in TLE. The optimal solution has a linear complexity. Here is procedure how you can derive linear from quadratic solution.Quadratic time solution

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Search Classroom

Algorithm to produce number series

I hope this helps you . This hint should help you... It isn't quite binary, but it is close. Let me know if you need any further help

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : ciops

2d path "shrink-wrap" algorithms

I hope this helps you . You could try using quadratic splines with anchors at the vertices at the start of a concave area, and a control point at a location inside the concave area.The control point location will have to be determined based on the lo

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : MikeG

Complexity of multiple variables

help you fix your problem Indeed, based on the definition, you must validate both cases. In this proof, as one of them is failed, so we can say that n^k is not in O(k^n) for any k and n. Although the other side is correct if you take k as a constant

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Hugo Hernan Buitrago

Algorithm to suggest correction for wrong input?

Hope this helps As far as I understood you have a list of actors and in case the user mistypes you want to give him the best match from your list.In that case the Levenshtein distance is a classic approach.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Grace Jones

What is the time complexity of the algorithm to check if a number is prime?

fixed the issue. Will look into that further Your method may have some slight problems (addressed below), but your approach should be O(n), where n is the value/size of the input to isPrime(). That is, in this brute force method, you are basically ju

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Mark

How to detect an inconsistent pattern of coordinates?

Does that help For simplicity lets assume that I have a list of X,Y coordinates. X has a limited range of 0-100 mm, and Y has 0 - inf mm. Every iteration a new list of coordinates is received. All the coordinates where the delta between their Y to th

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Tim Benninghoff

Find the median in an unsorted read-only array

To fix the issue you can do You can solve it using divide and conquer approach, find a random element in between the minimum and maximum, check if it's median, if the median is lower or higher than it, and reduce the problem to a smaller size only on

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : jehammon

What is the most efficient integer nth root algorithm for small numbers?

may help you . For n>2, a serious option is dichotomic search in a lookup-table. For n=3, the table takes 1290 entries (hence 11 dichotomic steps). For n=4, 215 entries (8 steps) and n=5, 75 entries (7 steps)…If I am right, you can even compress the

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : beng

divide and conquer algorithm for finding a 3-colored triangle in an undirected graph with the following properties?

it should still fix some issue It can be done in O(E*V) without using the partition property. Start by deleting all edges with the same color on both vertexes, this can be done in O(E). In the modified graph G', every triangle is a 3-colored triangle

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Comfly

How to get the K smallest Products from pairs from two sorted Arrays?

I wish did fix the issue. Instead of using the heap, try to generate products in the sorted order.Imagine an n*m grid formed by indices into the respective arrays. At any given point of time the grid is partitioned into the "inspected" and "not yet i

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Munir

What is the time complexity of the following method?

hope this fix your issue The algorithm loops until m reaches 0. In each iteration m is either halved (if it was even) or reduced by 1 (if it was odd). If the algorithm would just halve m in each iteration, then this would take log(m) steps (in the co

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Vrki

Find missing permutation

I hope this helps . You could try something like this: use your first 119 queries to query the first element of each "block", i.e. the 0th, 5th, 10th, etc. element count how often you find each letter, and where; there should be 24 permutations for e

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : noboruwatanabe

If a function is called more than million times in a second, print an error

Hope that helps If you get 900K calls in 0.1 seconds, and then the counter gets reset by timer, and then you get another 900K calls in 0.1 seconds, then you will have gotten 1.8M calls in a second, but you will fail to print an error.I would do somet

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : jch

Arranging the number 1 in a 2d matrix

I wish this helpful for you Hint: one possible solution utilizes Maximum Flow Problem by creating a special graph and running the standard maximum flow algorithm on it.If you're not familiar with the above problem, you may start reading about it e.g.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user180941

Algorithm to traverse k nodes of an undirected, weighted graph (and return to the origin) at the lowest cost

Hope that helps Since your problem includes the TSP for k=n as a special case in general it will be NP-complete. For small k you can adapt the dynamic programming solution of Bellmann (1962) to solve it in time O(2^k n^3).Let T(u,S) be the length of

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Kuer

Divide two strings to form palindrome

To fix the issue you can do Here is a possible solution considering that we cut the 2 strings in a common point. It runs in linear time w.r.t the string length, so in O(n).

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Simone

How to partition 2D-points into intervals (using only vertical lines)?

seems to work fine Here is an idea based on dynamic programming.With the following notations: (x_1, y_1), ..., (x_n, y_n) the points, with x_1

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Cosmin

How can I determine if a list of ranges covers a given range?

may help you . Since you will repeatedly call Continuous on the same set of ranges, it's a good idea to create a Condense method (or whatever you wish to call it) that will take a slice and return a new slice with the ranges sorted and any overlappin

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user150694

Picking out exacly one value from each row and column of a matrix

Hope that helps This is the problem of finding a maximum cardinality matching in a bipartite graph: the rows represent one set of vertices u_1, u_2, ..., u_N, the columns the other set v_1, v_2, ..., v_N, and there is an edge u_i -- v_j whenever ther

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : nabbed

Why is the given algorithm O(n^2)?

This might help you The outer loop iterates from 0 to N-1.The inner loop iterates from N down to i+1.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : CrimsonGore

How to Hash Value in Flutter Using SHA256?

will be helpful for those in need Hashing Value (String or Int OR etc...) in Flutter Heading , Import (Crypto) :

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user98832

Given a random int generator [0-5], generate [0-7]

it fixes the issue So this was an interview question.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : ap.

How to find Nth Armstrong number in less than O(n) time complexity?

this one helps. This may not be optimal solution, but As per this article,

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : billputer

Can we make the counting sort algorithm for n element with O(n) space complexity?

Hope this helps If we use an array for counting in counting sort then it requires space equal to the difference between the maximum and minimum key values. We can use hash-table, then we can reduce space complexity to linear relative to the number of

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Nick Coats

Find Top K Frequent Words In A Big Word Stream

will help you You can use trie. And store number of occurrences so far.The following tree corresponds to the following input:

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Techspirit

Find a Circle ((x,y,r)) that has maximum number of points 'on' it; given a set of points(x,y) in a 2D plane

To fix the issue you can do As a starting point, the simple O(N3) solution is to find the circle corresponding to each unique triple of points, while counting the number of occurrences of each circle you find.If a circle has N points on it, then you

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Imran

How to solve a matrix reachability recursion problem efficiently?

wish of those help This has a solution in O(min(m2n, mn2)) time and O(min(m2, n2)) space using dynamic programming.The idea is to consider angled "strips" that look like this (in bold):

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Don Changer

Count number of subsets having cumulative XOR less than k

it should still fix some issue Depending on the constraints of the problem, there are several viable ways to approach it: As you pointed out, if N is small enough, trying all possible subsets in O(2^N) will yield the intended result. If the values in

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : vdavidovski

Significance of selection sort

Does that help It is simple to write and intuitive for people to understand It is the closest to the way real humans approach sorting lists. It functions in-place in memory After n iterations you know the first n elements are sorted. After the first

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : user160048

How to find trend (growth/decrease/stationarity) of a data series

hope this fix your issue I am trying to extract the OEE trend of a manufacturing machine. I already have a dataset of OEE calculated more or less every 30 seconds for each manufacturing machine and stored in a database. , You could go for asliding av

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : CrimsonGore

Finding an optimal solution for targeting ships in a naval engagement

help you fix your problem Linear programming will do the job perfectly here. In this case, the decision variables are integers, so we are dealing with ILP.Here is a small description on how to model your problem as a linear program.

TAG : algorithm

Date : January 02 2021, 06:48 AM , By : Arun Thakkar