Data dodania  Pytanie  

20180214 07:02 
Swift how does my function exceed O(n)?
» I am trying to work on a leetcode problem that asks for Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appe... ^{(1) odpowiedzi} 

20180213 16:02 
Iterate through 2d array of booleans and leave only the largest contiguous "2D blob of ones"
» Ok, so the question is kind of awkwardly phrased, but I hope this will clear things up. I have this sample 2d array. $array = array( array(1, 0, 0, ... ^{(3) odpowiedzi} 

20180213 04:02 
Multiple sort numeric before string
» I would like to know how to sort numeric before string. I use array_multisort to sort my array. There is my sample data $arr = [ [ 'comp... ^{(2) odpowiedzi} 

20180211 16:02 
Seperate num to elements
» I'm trying to 'separate' a number into X elements. I mean, if my number is 12 and my desired element count (X) is 6, I want to separate for each elem... ^{(2) odpowiedzi} 

20180211 14:02 
Java  Check if array is sorted descendant
» I need to check if array was sorted strictly descendant. I wrote following code public boolean isSortedDescendant(int [] array){ if ((array.lengt... ^{(1) odpowiedzi} 

20180208 01:02 
Finding the odd number out in an array
» I am trying to solve a problem where I'm given an array, such as [0, 0, 1, 1, 2, 2, 6, 6, 9, 10, 10] where all numbers are duplicated twice, excluding... ^{(8) odpowiedzi} 

20180206 12:02 
Implement tailrecursive List operations
» I fear I've missed something "standard" but I did try, honest! I have been trying to understand how to implement efficient, tailrecursive, operation... ^{(3) odpowiedzi} 

20180206 04:02 
Group array of items by their distinct id
» How do I go about rearranging my array to by organized by shirt size: [ { shirt_id: 1, size: "small" }, { shirt_id: 1, size: "medium" }, { shi... ^{(2) odpowiedzi} 

20180205 11:02 
Python  inefficient spatial distance calculation (how can it be speed up)
» I am currently trying some geocoding in Python. The process is the following: I have two data frames (df1 and df2, houses and schools) with latitude a... ^{(2) odpowiedzi} 

20180204 20:02 
C++ time spent allocating vectors
» I am trying to speed up a piece of code that is ran a total of 150,000,000 times. I have analysed it using "Very Sleepy", which has indicated that t... ^{(1) odpowiedzi} 

20180131 20:01 
Java booleanalgorithm to check wheter number of digits is even
» I´m trying to write a recursive method that returns true, if the count of digits of n displayed as a binary number is even and false if it is odd. I ... ^{(4) odpowiedzi} 

20180130 18:01 
How does this put implementation work with q instead of p
» We are implementing the put part of Algorithm A from Functional Programs for Generating Permutations (Topor, 1982). This is our implementation. It pas... ^{(2) odpowiedzi} 

20180130 07:01 
Faster way to get substring in python?
» I am coding Skew Algorithm to construct the Suffix Array and I have a long string (length >= 4000). In Skew Algorithm, I have to construct the Triples... ^{(3) odpowiedzi} 

20180126 22:01 
Why my Binary Search implementation in Scala is so slow?
» Recently, I implemented this Binary Search, which is supposed to run under 6 seconds for Scala, yet it runs for 1213 seconds on the machine that chec... ^{(1) odpowiedzi} 

20180125 13:01 
Comparing computational speed of these two short codes
» In the two versions of the code, both v1 and v2 are large vectors (length ranging from 1,000 1,000,000 with len(v1)=len(v2)). I expected code 2 to be ... ^{(2) odpowiedzi} 

20180124 18:01 
Efficiency of Sieve of Eratosthenes algorithm
» I am trying to understand the "Sieve of Eratosthenes". Here is my algorithm (code below), and a list of features that I cannot understand (in order). ... ^{(2) odpowiedzi} 

20180123 21:01 
How to count the number of reduced proper fractions fast enough?
» I am currently solving a mathematical problem in which I need to count the number of reduced proper fractions with both numerator and denominator more... ^{(6) odpowiedzi} 

20180123 20:01 
Faster way to read/write a std::unordered_map from/to a file
» I am working with some very large std::unordered_maps (hundreds of millions of entries) and need to save and load them to and from a file. The way I a... ^{(5) odpowiedzi} 

20180120 20:01 
Recursive and random grouping a list
» I'm trying to write a function which creates dichotomously grouped list, f. ex. if my input is as following: [a, b, c, d, e, f, g, h] I want to ... ^{(2) odpowiedzi} 

20180120 03:01 
Implementing unification and skipping variables
» I'm working on an implementation of the usual unification algorithm in the usual way: recursive descent through expression trees, adding variable bind... ^{(2) odpowiedzi} 

20180118 14:01 
Optimized argmin: an effective way to find an item minimizing a function
» Let us say I've got a collection of items and a score function on them: struct Item { /* some data */ }; std::vector<Item> items; double score(... ^{(3) odpowiedzi} 

20180106 17:01 
How Python execute [list] * num? what's time complexity and memory complexity?
» I am new to Python. I was recently confused by a syntax "[list] * k". I want to understand how Python actually executes it. Example: >>> l ... ^{(1) odpowiedzi} 

20180105 13:01 
What's the best way to enumerate permutations of deck of cards?
» I'm looking to make a function that would assign a value to a specific shuffle of cards. The function has to be bijective. The deck has 52 cards so ... ^{(1) odpowiedzi} 

20180104 17:01 
Dynamic Programming with Scala
» To practice Scala I wanted do solve simple dynamic programming exercises with Scala. For some exercises I already wrote a Python implementation. Using... ^{(3) odpowiedzi} 

20180103 17:01 
High performing container for storing a high number of objects
» I am looking for an ideal data container for with following objectives: The behavior of the container must be sort of like Queue, with the following ... ^{(2) odpowiedzi} 

20180102 14:01 
Finding the longest substring regex?
» Someone knows how to find the longest substring composed of letters using using MatchCollection. public static Regex pattern2 = new Regex("[azAZ]"... ^{(6) odpowiedzi} 

20171231 16:12 
Jquery bubble sort on a table
» I have got this table that has rows of numbers. Now I want to create a jQuery function that'll sort this table once th is clicked and I want to do tha... ^{(2) odpowiedzi} 

20171231 01:12 
Understanding this polynomial division algorithm in a functional language
» **This is an algorithm that is implemented in a rather archaic language, standard ML. I have difficulty understanding this algorithm: fun polyquotrem... ^{(1) odpowiedzi} 

20171229 09:12 
Get minimum Euclidean distance between a given vector and vectors in the database
» I store 128D vectors in PostgreSQL table as double precision []: create table tab ( id integer, name character varying (200), vecto... ^{(2) odpowiedzi} 

20171222 22:12 
How to find smallest positive integers to make digits monotonic?
» I found a programming problem I was unable to solve. I have been given a set A of integers. For all numbers x in A, find the smallest positive integer... ^{(2) odpowiedzi} 

20171220 01:12 
Creating a pair of its order, value in a list in python
» Let's assume that we have a following list: [3, 1, 2, 100, 5] (this is just an example, could be any list containing real numbers of arbitrary len... ^{(5) odpowiedzi} 

20171219 18:12 
javascript  find subset that gives maximum sum under a certain limit (subset sum )
» I have an array with some integer values, and I need to get a subset of them that gives me the maximum sum that is inferior to a given value. So let's... ^{(3) odpowiedzi} 

20171219 01:12 
QuickSort and MergeSort performance on Sequential data fit in memory vs Slow to Access Sequential data on disk
» The following quote is from "Comparison with other sort algorithms" section from Wikipedia Merge Sort page On typical modern architectures, effic... ^{(1) odpowiedzi} 

20171213 03:12 
BST O(NLogN) build proof
» I'm trying to study for a test and I know that a single insertion is O(logn) and the height of the tree is n, so the comparisons would make the time ... ^{(1) odpowiedzi} 

20171209 19:12 
How can I find the missing integer in a string of random nonrepeating integers in a range
» I'm having trouble even beginning to think of how to do this. I need to find a missing number in a string of random numbers that don't have separator... ^{(3) odpowiedzi} 