I need some help with a method i'm writing for a project. the method changes a phone number into a list of text strings. You know that 2-9 have letters associated with them on a phone. i would like to make a converter that will change a 7 digit number to a list of strings. i would like to see all possibilities. i already cut out all th...
Given n points on a 2-D plane, what is the point such that the distance from all the points is minimized? This point need not be from the set of points given. Is it centroid or something else? How to find all such points(if more than one) with an algorithm? ...
Perverse Hangman is a game played much like regular Hangman with one important difference: The winning word is determined dynamically by the house depending on what letters have been guessed. For example, say you have the board _ A I L and 12 remaining guesses. Because there are 13 different words ending in AIL (bail, fail, hail, jail, ...
I am writing a program in C. I want to find a solution by minimizing expression D1+D2+......+Dn where Di's are distances calculated by distance formula between 2 points. The above expression is in x & y variables Now I will differentiate this expression and find the solution. My doubt is: since in the above expression, all Di's will...
Algorithm Consider this layout: +-------------+ | | | | | +--+ | | |##| | | |##| | | +--+------+ | |######| | |######| +------+------+ The black part is the occupied space. Now I need an algorithm that returns the largest remaining rectangular spaces. (Ordered from top to bott...
Imagine hexagonal space with 3 dimensions. Each tile has coordinates XYZ. I need to select a given cell neighbors in the same plane. With SQL it's looks like: $tbDir = $y % 2 == 0 ? -1 : 1; $result = db_query('SELECT x,y,z FROM {cells} WHERE x = %d AND y = %d AND z = %d OR x = %d AND y = %d AND z = %d OR ...
I need to implement a string-matching algorithm to determine which strings most closely match. I see the the Hamming distance is a good matching algorithm when this fixed-length is obtainable. Is there any advantage in the quality of matching if I were to use the Levenshtein distance formula instead? I know this method is less effic...
Given an array A of integers, find any 3 of them that sum to any given T. I saw this on some online post, which claims it has a O(NlogN) solution. For 2 numbers, I know hashtable could help for O(N), but for 3 numbers, I cannot find one. I also feel this problem sounds familar to some hard problems, but cannot recall the name and th...
Hi All, I did some searching and was not able to find any information regarding this implementation versus every other one I have seen. function sieve($top) { for($i = 11; $i<$top; $i+=2) { if($i % 3 == 0 || $i % 5 == 0 || $i % 7 == 0) { continue; } echo "$i <br /...
Hi. What would be the best method to compare 2 bitmaps and get the correlation between the 2 (0 being completely different and 1 being exactly the same) in Unity3d on the iPhone? I am using C# since documentation says that using Boo or UnityScript will increase the size of the application. What I need is something similar to the fingerp...
I often find it is difficult to find something that I know the logic sounds familar but cannot recall the name. Using the existing string based search engine just won't get you good result as most of the time the logic is expressed in a totally different way. I understand the generic problem is a unsolvable AI problem. The question ...
Say I have two maps, each represented as a 2D array. Each map contains several distinct features (rocks, grass, plants, trees, etc.). I know the two maps are of the same general region but I would like to find out: 1.) if they overlap and 2.) if so, where does this overlap occur. Does anyone know of any algorithms which would help me ...
I was working on this graph problem from the UVa problem set. It's a single-source-shortest-paths problem with no negative edge weights. From what I've gathered, the algorithm with the best big-O running time for such problems is Dijkstra with a Fibonacci heap as the priority queue, although practically speaking a binary heap is easier t...
The N-Queens Problem: This problem states that Given a chess board of size N by N. Find the different permutations in which N queens can be placed on the Board without any one killing each other. My question is: What is the maximum value of N for which a program can calculate the answer in reasonable amount of time? Or what is the lar...
I have a problem where I really need to be able to use finite automata as the keys to an associative container. Each key should actually represent an equivalence class of automata, so that when I search, I will find an equivalent automaton (if such a key exists), even if that automaton isn't structurally identical. An obvious last-resor...
Hi Everyone, I have a list of strings whose values come from a fixed set. I need to sort this list in an arbitrary order. The order of the set is specified by another list of all possible strings, sorted in order in an array. Here is an example: my @all_possible_strings_in_order = ('name', 'street', 'city','state', 'postalcode'); ...
Hi, I have a two ArrayList given below as sample. AccVO: compareKey,Amount fields List 1: AccVO[001,500] AccVO[002,600] AccVO[003,800] List2: AccVO[001,100] ...
I am looking for a good strategy of dealing with database deadlocks from within a Java 6 application; several parallel threads could, potentially, write into the same table at the same time. The database (Ingres RDMBS) will randomly kill one of the sessions if it detects a deadlock. What would be an acceptable technique to deal with the...
After reading this question I started to wonder: is it possible to have a shuffling algorithm which does not modify or copy the original list? To make it clear: Imagine you are given a list of objects. The list size can be arbitrary, but assume it's pretty large (say, 10,000,000 items). You need to print out the items of the list in ra...
Given data values of some real-time physical process (e.g. network traffic) it is to find a name of the function which "at best" matches with the data. I have a set of functions of type y=f(t) where y and t are real: funcs = set([cos, tan, exp, log]) and a list of data values: vals = [59874.141, 192754.791, 342413.392, 1102604.284...