Questions tagged [array]
An array is an ordered data structure consisting of a collection of elements (values or variables), each identified by one (single dimensional array, or vector) or multiple indexes.
2,114
questions
2
votes
2
answers
41
views
Calculating the sum of all k-sized sub-arrays in an array using sliding window algorithm
I need to calculate the sum of all k-sized sub-arrays in an array using sliding window algorithm. Is that a valid sliding window algorithm? If not, why?
...
- 21
0
votes
0
answers
52
views
How can I further optimize this code regarding array operations? [closed]
In the following code I am performing XOR operation on two arrays result and DB, result is accessed after an offset called rotate1 in following. As you can see I am already doing AVX2 and loop ...
2
votes
2
answers
117
views
Counting duplicate elements in two sorted arrays
I've been working on an assignment that involves optimizing a duplicate finding algorithm for sorted arrays, and I'd like to get your thoughts on the implementation. Here's the code I've come up with:
...
- 21
2
votes
0
answers
34
views
Reusable storage for array of objects V4
Here is a thirdfollow up on Reusable storage for array of objects, Reusable storage for array of objects V2 and Reusable storage for array of objects V3, taking into account the provided answers.
The ...
- 299
1
vote
1
answer
45
views
Reusable storage for array of objects V3
Here is a second follow up on Reusable storage for array of objects and Reusable storage for array of objects V2, taking into account the provided answers.
The following code should be compliant at ...
- 299
3
votes
1
answer
48
views
Reusable storage for array of objects V2
Here is a follow up on Reusable storage for array of objects, taking into account the provided answers.
The following code should be compliant at least with gcc, <...
- 299
0
votes
0
answers
36
views
Finding the pivot point in a rotated array which has been shifted from kth element
I'm trying to solve the following problem:
Joker has a deck of n cards, each with a value written on it. The cards are arranged in ascending order from top to bottom. Joker's master performs a hidden ...
- 212
4
votes
2
answers
331
views
Reusable storage for array of objects
My goal is to have a memory pool non-template class that is used to store arrays of objects.
The same memory pool object must be reusable for a different array (difference size, different type and/or ...
- 299
1
vote
0
answers
43
views
Javascript basic search engine recipes
I have made a search engine for recipes. Requirements for this JS Project are as follow:
Create a function called searchRecipes that takes all recipes and an ...
- 11
3
votes
3
answers
996
views
Small code exercise with 3D arrays in C
I wrote a small program that initializes a 3D array in C based on command-line arguments and prints it. I did my best to avoid undefined behavior and memory errors. I wrote comments as if I had an ...
- 449
3
votes
2
answers
88
views
Quickselect algorithm implementation and its time-complexity
I wrote this code to find kth smallest element in the array by renowned algorithm quickselect. Here is the link where you can see the working code.
What points are there to be improved? Could you ...
1
vote
0
answers
68
views
Performant 2D Grid Cluster Finder Algorithm
I would like to vastly improve the speed of the second part of this algorithm to find clusters of points on a 2D grid.
Each point is represented by a Region on the ...
5
votes
4
answers
2k
views
Automate the boring stuff with python - Character picture grid
Character Picture Grid
Say you have a list of lists where each value in the inner lists is a one-character string, like this:
...
- 159
-2
votes
2
answers
176
views
Count the number of mismatches between two arrays [closed]
This function may compute the amount of unequal elements of two char-arrays of the length n:
...
- 147
2
votes
1
answer
86
views
3
votes
1
answer
65
views
Dyalog APL dyadic operator deriving ambivalent function to pair two function results
I'm writing a small utility operator which applies two functions to an argument pair and strands the results. The pair can either be given as two arguments or as a single argument with two elements. ...
- 656
0
votes
1
answer
54
views
The Matrix Winds In
The Problem: Given an N by M Matrix, Create an Anti-Clockwise Traversal Path that winds in all the way into the Matrix
Example: The Matrix is 9 by 5
Output:
...
3
votes
0
answers
41
views
extracting values from an array of nested objects without duplicates
I have my solution for the below usecase but I would like to know whether is any other effective solution for the same.
My Data:
...
- 131
4
votes
3
answers
425
views
Determine whether two arrays have the same elements with the same multiplicities
I have written a Python function called comp that checks whether two given arrays have the same elements, with the same multiplicities. The multiplicity of a member ...
- 397
0
votes
1
answer
43
views
Optimizing the Dig Pow function
I have written a Python function to solve the Dig Pow problem, where the goal is to find a number k such that the sum of each digit of n raised to a specific and ...
- 397
2
votes
2
answers
60
views
Given a sorted list of integers, find the highest count of elements between an indeterminate but fixed size range
I'm trying to optimize a function that takes a sorted list of integers and tells me what is the maximum number of elements in the list between any definite size range. To be clear, the range itself ...
5
votes
3
answers
753
views
Merge Sorted Array in Rust
I was solving this task https://leetcode.com/explore/learn/card/fun-with-arrays/525/inserting-items-into-an-array/3253/
The main idea is to merge two sorted arrays (more details in the site)
Example:
<...
- 375
1
vote
1
answer
119
views
swap two different length group of variable in array
The code below swaps two different-length groups of variables of the same array in the same array.
Is there any other method to achieve this that is less heavy or less redundant?
...
- 11
5
votes
2
answers
119
views
concatenate values and delete the remaining rows using arrays
the below code used to:
Concatenate the values on a specific column "N" depend on the value of column "A" then delete the remaining rows.
It works, but with range of 30k rows the ...
- 275
0
votes
1
answer
28
views
Mangle words to bytearray of lo/hibytes
I would like to refactor the following code snippet adapted from a project I'm involved. It is part of a code to control power outlets via network. The code snippet was written by myself based on the ...
- 141
4
votes
3
answers
2k
views
Custom array class in C++
I wrote a custom array class in C++ to suit my personal use case. The main important rule in this project is that no unassigned element is allowed between 2 assigned elements; please review for ...
- 519
1
vote
2
answers
45
views
Extend native `Array` instances
I need/want to extend created array instance, to add extra methods that i see as useful.
class.labels.js
...
- 133
5
votes
2
answers
268
views
PHP Fisher-Yates shuffle with random_int
The PHP manual states that the regular shuffle() function isn't cryptographically secure, but that random_int() is. I thought, ...
- 53
5
votes
1
answer
396
views
Dynamic array type using void pointers C
I made my own dynamic array type using void pointers. I'd like to know what you think of my implementation. void pointers are nice but I fear they may be inefficient. The compiler cannot tell what ...
- 65
8
votes
4
answers
259
views
Array List C implementation
I want to show you my implementation of the array list in C. Is there something I can improve or fix?
Header
...
- 301
6
votes
2
answers
128
views
First attempt at making a sobel edge detection filter in c
I made a borders filter in C. It works properly, but I think it could be optimized and better designed; the formatting is abysmal. It uses too many lines for the border cases and has too many ...
- 63
0
votes
0
answers
63
views
Bruteforce proof of an arithmetic expansion scheme expression in array lists (Java)
Given a list of, say, integers, one way to implement such a list is to rely on an array under the hood. When we are adding elements to the array list, we might need to make the internal array larger. ...
- 27k
2
votes
2
answers
168
views
Quick Sort Program
Quick sort is a sorting algorithm in which we select any random element as pivot from the array and we do the partition of the array around that pivot. Basically we place all the elements smaller than ...
5
votes
4
answers
434
views
RGB Image Utility Class
I am writing a utility class to store RGB images and do a few utility functions as a way to learn C++.
...
3
votes
1
answer
91
views
Iteratively paste values from spreadsheet tabs into empty spreadsheet
Basically below code is taking first 7 tabs from my current sheet and pasting them as values in a blank excel sheet with same tab names and saving them in a specific folder by filename I specified. ...
- 31
1
vote
1
answer
55
views
Transform an array into object and set index for an unique key in javascript
I have a method that merges keys and indexes from an array into an object.
I'm stuck with ways to compress this method, and I don't know what I can do to make it simpler.
Goal
get an array of objects ...
- 155
0
votes
1
answer
91
views
Printing Permutations
Following is a leetcode problem:
Given an array nums of distinct integers, return all the possible permutations. You can return all the possible permutations. You can return the answer in any order.
...
2
votes
1
answer
51
views
Helper functions to get, set and remove from Firefox browser storage. Also, to get, push and remove from lists stored in the database
I am making a plugin for Firefox, this is (more or less) my first time working with JavaScript. Is this a reasonable design for working with both values and lists in a database?
...
2
votes
1
answer
94
views
C generic typesafe dynamic array (vector) try 2
The previous generic dynamic array I asked a review for here was written using only the preprocessor and so while the array itself was type-safe, all the manipulating macros where not.
In this try I ...
- 179
2
votes
1
answer
72
views
An implementation of Givens method for diagonalising symmetric matrices
So I tried to create a code which aims to diagonalise symmetric matrices via Givens algorithm. The program only works for symmetric matrices, for we know a symmetric matrix is always diagonalisable, ...
- 121
2
votes
2
answers
78
views
Follow-up about computing lp norm with MPI
As pointed out in the answer by Victor Eijkhout to this question, the fact I am broadcasting the same vector to each process is against the MPI principles and, most importantly, will be a bottleneck ...
- 217
2
votes
1
answer
339
views
Compute lp-norm of a vector in parallel with MPI
I'm trying to solve the following exercise:
Compute in parallel with MPI the lp norm of a vector of a predefined size N ...
- 217
3
votes
1
answer
132
views
Swift - efficient array searching
I am trying to find a way to search an Int array (all numbers are > 0) and identify sequences where the sum of each element is a specific number. One element can ...
- 179
10
votes
5
answers
2k
views
Implementation of a two-dimensional array in C
I implemented a two-dimensional array in C and would like to know if the implementation is sound in terms of
Memory management
Potential bugs and other side effects that I missed
Code style (...
- 1,125
3
votes
1
answer
114
views
How can I condense my code in node.js for sorting unique values within an array?
Kattis problem - ("I've been everywhere")
I would highly recommend looking at the problem through the link, however I will summarize it a bit here and explain the functionality of each part ...
- 33
4
votes
2
answers
218
views
Robust input for lottery tickets
I've made a method that provides a robust way for a user to fill out a lottery ticket. During this process I found out that Java also provides syntax for labels. That was very astounding for me. But I ...
- 2,154
1
vote
1
answer
145
views
C# Get All Diagonals Jagged Array
How can I improve this?
The idea is to store every left to right diagonals in a list
Not looking for a more efficient algorithm instead something readable, LINQ perhaps?
input:
3, 1
2, 5, 7
1, 5, 8, 3,...
- 103
2
votes
1
answer
88
views
Multidimensional array in Java
I have this multidimensional array that generalizes vectors and matrices:
com.github.coderodde.util.MultidimensionalArray.java:
...
- 27k
4
votes
3
answers
357
views
Removing repeating rows and columns from 2d array
This is a real problem I had to fix recently. Imagine having generic array where you can have duplicate columns and rows.
You want to remove those duplicates as long as they are next to each other.
<...
- 2,568
1
vote
1
answer
116
views
Array Implementation In JavaScript
Review
I have written my own implementation of Array in JavaScript with the basic functionalities. Can anyone please review this code and point out the mistakes/how to make the implementation better?
...
- 253