All Questions
Tagged with performance algorithm
983 questions
4
votes
4
answers
423
views
Finding Special Parts in a Word
Task description:
Imagine you have a long word made up of small letters like "a", "b", "c", ancd so on. Let’s call this word a puzzle word.
We want to look at all the ...
- 373
2
votes
0
answers
71
views
backward induction algorithm computation
Is there a way to significantly speed-up this code?
I'm solving a dynamic programming model using a backward induction algorithm. A crucial step is to calculate the current-period value function (VF), ...
- 121
2
votes
0
answers
134
views
How to make this arbitrary precision π calculator using Machin-like formula run faster?
Two days ago (or yesterday depending on your timezone) was π-day. So I thought it was a good day to calculate π.
I used Machin-like formula to calculate π, in homage of William Shanks, who calculated ...
- 3,396
4
votes
1
answer
133
views
otsu_threshold Template Function Implementation for Image in C++
This is a follow-up question for An Updated Multi-dimensional Image Data Structure with Variadic Template Functions in C++, histogram Template Function Implementation for Image in C++, Histogram of ...
- 7,068
3
votes
1
answer
91
views
Merge discrete integer intervals
What it does
The code starts with a set of integer intervals, and can add new intervals (possibly by updating existing intervals). Essentially, it is a bit array whose index starts at ...
- 1,158
2
votes
1
answer
221
views
Pattern search algorithm for infinite integer string in R
Let X = "1234567891011..." the infinite string contains all positive integers. str is a sequence of digits. We are asked to find the first location in X that str appears.
I have tried the ...
- 21
8
votes
3
answers
2k
views
Is set of integers closed under the operation of subtraction?
I was working on a problem, but my solution did not pass the time limit test.
Problem
Let's say a set of integers is closed under the operation of
subtraction if for two distinct elements of this set ...
- 89
2
votes
3
answers
198
views
Efficiently tagging first and last of each object matching condition
How can I make the code more readable and more efficient? (provided code is O(n²) time, but intuition says it can be pre-processed and done in O(n) time)
Description
it tags the first and last of ...
- 1,158
3
votes
1
answer
89
views
Check which sinks are connected in the pipe system using Python
It would be very helpful to me as a beginner if I could get feedback on my code, specifically about the efficiency of algorithm used and potential improvements in code quality.
Code context:
There is ...
- 111
5
votes
4
answers
1k
views
Fast circular buffer [closed]
I'm working on a modern C++20 solution that does two things:
It accumulates a sliding window of input data points; the sliding window's size is fixed and known beforehand. Data has strict ordering ...
- 195
4
votes
1
answer
140
views
Efficient polynomial multiplication in Python
I'm practicing problems for the ICPC competition, and one of the problems requires solving it by using an FFT to compute the product of two polynomials efficiently. Since this is for the ICPC ...
- 175
1
vote
2
answers
116
views
A simple performant factorial function
I am new to algorithm and data structure. After a little introduction to the topic, I have decided to implement a function called calculateFactorial, which takes an integer and calculates its ...
3
votes
1
answer
237
views
Leetcode: Number of Islands - BFS (Queue vs Recursion)
I was playing around with leetcode's Number of Islands.
As per the challenge's description:
Given an m x n 2D binary grid grid which represents a map of '1's
(land) and '0's (water), return the ...
- 361
3
votes
2
answers
95
views
Optimizing a Function to Check Pronic Numbers in JavaScript
I've written a function in JavaScript to check whether a given number is a Pronic number. A Pronic number, also known as an oblong number, rectangular number, or ...
- 573
6
votes
1
answer
347
views
Codeforces: D2. Counting Is Fun (Hard Version)
The code works okay for the following problem.
Problem
An array 𝑏 of 𝑚 non-negative integers is said to be good if all the elements of 𝑏 can be made equal to 0 using the following operation some (...
- 244