I am looking for the most efficent way of solving the following Problem: given an array Before = { 8, 7, 2, 1} and an array After ={1, 3, 8, 8} find the added and the removed elements the solution is: added = 3, 8 removed = 7, 2 My idea so far is: for i = 0 .. B.Lenghtt-1 { for j= 0 .. A.Lenght-1 { ...
GUID are generated by the combination of numbers and characters with a hyphen. eg) {7B156C47-05BC-4eb9-900E-89966AD1430D} In Visual studio, we have the 'Create GUID' tool to create it. I hope the same can be created programmatically through window APIs. How GUIDs are made to be unique? Why they don't use any special characters like #,...
Greetings, Any input on a way to divide a std::vector into two equal parts ? I need to find the smallest possible difference between |part1 - part2|. This is how I'm doing it now, but from what you can probably tell it will yield a non-optimal split in some cases. auto mid = std::find_if(prim, ultim, [&](double temp) -> bool { if(...
I have several ArrayLists of Integer objects, stored in a HashMap. I want to get a list (ArrayList) of all the numbers (Integer objects) that appear in each list. My thinking so far is: Iterate through each ArrayList and put all the values into a HashSet This will give us a "listing" of all the values in the lists, but only once I...
hello, i have an array of points in 3d (imagine the trajectory of a ball) with X samples. now, i want to resample these points so that i have a new array with positions with y samples. y can be bigger or smaller than x but not smaller than 1. there will always be at least 1 sample. how would an algorithm look like to resample the orig...
I have N people who must each take T exams. Each exam takes "some" time, e.g. 30 min (no such thing as finishing early). Exams must be performed in front of an examiner. I need to schedule each person to take each exam in front of an examiner within an overall time period but avoiding a lunch break, using the minimum number of examiners...
Hello, I have several huge sorted enumerable sequences that I want to merge. Theses lists are manipulated as IEnumerable but are already sorted. Since input lists are sorted, it should be possible to merge them in one trip, without re-sorting anything. I would like to keep the defered execution behavior. I tried to write a naive algor...
Okay, here is my problem: Im implementing an algorithm in Java and part of it will be following: The Question is to how to do what I will explain now in an efficient way. given: array a of length n integer array perm, which is a permutation of [1..n] now I want to permute the array a, using the order determined by array perm, i.e. a...
Hi all, I've got the following recursion: T(n) = T(n/3) + T(2n/3) + O(n) The height of the tree would be log3/2 of 2. Now the recursion tree for this recurrence is not a complete binary tree. It has missing nodes lower down. This makes sense to me, however I don't understand how the following small omega notation relates to the co...
I am implementing some math algorithms based on lists of points, like Distance, Area, Centroid, etc. Just like in this post: http://stackoverflow.com/questions/2227828/find-the-distance-required-to-navigate-a-list-of-points-using-linq That post describes how to calculate the total distance of a sequence of points (taken in order) by es...
Profiling my cpu-bound code has suggested I that spend a long time checking to see if a container contains completely unique elements. Assuming that I have some large container of unsorted elements (with < and = defined), I have two ideas on how this might be done: The first using a set: template <class T> bool is_unique(vector<T> X) {...
Is there a simple algorithm to encrypt integers? That is, a function E(i,k) that accepts an n-bit integer and a key (of any type) and produces another, unrelated n-bit integer that, when fed into a second function D(E(i),k) (along with the key) produces the original integer? Obviously there are some simple reversible operations you can...
I want to compare the keys in a hash of parameters against an array of elements for a match. For example: params = {"key1", "key2", "key3"} params_to_match = ["key2","key3"] I could do this, but I'm sure there is a much more elegant way to acheive the same result params.each_key{|key| if params_to_match.include?(key.to_s)...
I was playing around with .Net reflector today and realized that Miicrosoft's entire Expression suite is written in .Net. As a result I was pretty much able to see the underlying code for expression. This makes it far easier than binary to break copy protection. I think that that's a big deal. Is it generally recommended to make commerci...
hi friends. I am supposed to write and algorithm which uses recursion (Divide-And-Conquer) to multiply two arrays.These arrays hold big Numbers that are greater than long(int 64) or double capacity. Would please help to write this algorithm in C#? ...
Hi. I was wondering if there was an algorithm for counting "most frequent items" without having to keep a count of each item? For example, let's say I was a search engine and wanted to keep track of the 10 most popular searches. What I don't want to do is keep a counter of every query since there could be too many queries for me to count...
Please share some good websites where I can learn more on String Processing Techniques and could grill myself more into different kinds of algorithm available in this field.. ...
I have a warehouse in which I keep goods. Each article occupies given volume of warehouse space and costs give amount of dollars. Now, because warehouse is full and I'm expecting new delivery, I have to free some space - no less than the new delivery will occupy, but I also have to minimize my loses. In other words, I have to empty at l...
This was one of the interview questions asked. How to find the length of a linked list that is having cycle in it. I know how to calculate whether a linked list has a cycle or not using Hare and Tortoise technique. I even know how to calculate the length by storing the addresses in a hashset. The running time of the Algorithm should be O...
I have been some time thinking how to resolve this problem, but out of ideas i prefer expose it for help. I have 2 tables (linq to sql) A and B, A have a many relation with B, so A have a property EntitySet of B A have the following properties: CreateDate (Datetime) ModificateDate (Datetime) Bs (EntitySet<B>) B have the follow...