Merge sort is an O(n log n) comparison-based sorting algorithm.

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Natural mergesort

This is a problem from Robert Sedgwick's Algorithms book: Write a version of bottom-up mergesort that takes advantage of order in the array by proceeding as follows each time it needs to find two ...
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Fast merge sort in JavaScript

When developing a user interface that allows sorting by various different fields, I noticed that Array.prototype.sort() is extremely slow for large inputs. After ...
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Parallel natural merge sort

Continuing working on Natural merge sort, I have parallelized it. Requires \$\Theta(N)\$ space and runs in $$\Omega(N + \frac{N}{P}) \cap \mathcal{O}(N + \frac{N}{P}\log_2\frac{N}{P})$$ time, where ...
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Natural merge sort - follow-up

The previous iteration at Natural merge sort Now my code relies on C++14 and looks like: natural_merge_sort.h: ...
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Natural merge sort

Note: the next iteration at Natural merge sort - follow-up I have compiled natural merge sort algorithm from Java to C++. Natural merge sort sacrifices at most \$2N\$ amount of work in order to ...
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Mergesort using map-reduce, multithreads, buffers and condition variables

I wrote a map reduce program which uses multi threads, bounded buffers, condition variables. It works perfectly for some types of inputs. Is there any way I can improve it? Any help is appreciated! ...
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Merge sort implementation: sorting feels clunky

I got bored and decided to make a merge sort from scratch. I like everything, except for my "merging" of the two arrays into a sorted array inside the for loop. I ...
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Implementation of the merge_sort - comparing the timing of an array versus a vector

I'm going through the book Introduction to Algorithms. I made a comparison between merge-sort for an array of integers versus a vector. Could I have structured this program better? Why is the ...
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Mergesort a LinkedList

I have made an attempt to write the mergesort routine on a LinkedList in Java. It will be great if somebody can review my implementation and point out the issues ...
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59 views

Sort a linked list with merge sort in C

This is my version of a linked list in C. The function mergeSort requires a reference to the first and to the last nodes, as well as the indices of the first and ...
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142 views

Mergesort bottom-up

I am looking for suggestions on how to improve my mergesort. My teacher explained the recursive mergesort and left the bottomUp one as an assignment. I have ...
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Classic sorting algorithms [closed]

I implemented the classic Sorting Algs in JS for practice. I come from a C++/Java background. Just wanted to make sure I didn't miss anything or if there was a 'better' JS way of doing it. Also, I ...
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Merge sort implementation and improvements

I would like your opinion on my Java implementation of the merge sort algorithm on an integer array, since I'm not really into algorithms I'd like to know from you if this is a correct implementation ...
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Is this an efficient way to implement Merge Sort in C++?

I am studying C++ and I wrote the following Merge Sort algorithm. I need some comments from skilled C++ programmers to understand where it can be improved, in terms of execution time, memory usage and ...
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Merge sort in C++ with iterators

I implemented merge sort with C++ and would like to get some feedback. ...
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Merge Sort Implementation: Space Usage

I have made a merge sort algorithm but am unsure of the 'Space Usage' of the algorithm. ...
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Merge sort for a List<T>

Is this merge sort following good coding standards? What are some improvements I can make to make it cleaner? ...
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91 views

Merge sort optimization and improvement

How to optimize this merge sort code to make it run faster? And how to call merge_sort function without user input by declaring necessary array in the code? ...
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Is this an optimal implementation of merge sort?

I am taking an algorithm course and we are to implement merge sort that handles list of elements with even or odd number of elements and handles duplication, so I wrote this function: ...
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Sorting function that also works with containers having only forward iterators

I was playing around with some code trying to implement a sorting algorithm in C++ that also works with singly linked lists. Since the merge routine of mergesort only scans forward, implementing a ...
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625 views

Merge sort with raw C++ array

Merge function: ...
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Mergesort with std::vector

I made a mergesort implementation based on this code. Please review my C++ version. ...
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3-way merge sort in Java

All those numerous merge sorts split the range in two halves. This is a modification that splits each range into 3 subranges. My demo suggests that 3-way merge sort is pretty efficient on large ...
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Natural merge sort in Java - follow-up

See the previous iteration: Natural merge sort in Java Arrays.java ...
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Natural merge sort in Java

Natural merge sort is a modification of merge sort that sacrifices O(N) to actually build a list of "runs" that may be defined as monotonically increasing or strictly decreasing contiguous ...
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288 views

Merge sort using sentinels

This is my implementation of recursive merge sort, using sentinels: ...
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75 views

Mergesort and validation

I have written an implementation of a Mergesort in Python3. An Ideone with the implementation is available. Any suggestions for improvement or any criticisms? ...
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Merge sort in Python

I've written a implementation of a merge sort in Python. It seems correct and I have tested it with this: ...
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Merge Sorting Lists

I'm fairly new to Java, arriving in the "future" from C and returning to type safety from Python. I'm looking for your suggestions to improve this code in the following areas: Correctness - are ...
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223 views

Merge sort in Golang

I am just starting out with golang. I implemented the merge sort algorithm just to practice. Any suggestions or criticisms regarding the coding style? ...
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107 views

External bottom up merge sort too slow

My external sort function works but it is way too slow. I think the bottleneck is the merge function. How can I make it faster. Is there a better merge function I can use for merging into a file using ...
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Merge Sort an integer array

I've implemented merge sort an integer array. Is it okay to use i,j,k as variable name for looping? Should I change them to more meaningful names? Overall, any further suggestions on this code? ...
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Merge sort efficiency

I've written this Java code to implement merge sort: ...
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602 views

Merge sorting linked lists

This works as expected and I want to get this code reviewed so that I can improve my coding ability. I am concerned about readability and the quality of the code ...
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Merge Sort Implementation in Java (that seems slow…)

I decided to write my own implementation of merge sort. Here is the code: ...
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File-based fixed-record merge sort

A problem posted here to Code Review prompted me to experiment with a general-purpose merge-sort algorithm for any fixed-length record data. External / File-based mergesort I answered that question, ...
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External / File-based mergesort

I've implemented an external mergesort to sort a file consisting of Java int primitives, however it is horribly slow (fortunately it does at least work). Very little happens in the sort method: it ...
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Merge sort in JavaScript

I implemented this merge sort in JS and noticed that for random integer numbers it's a lot faster than the build in sort functions of all the browsers I tested (Chrome, FF, IE). Does anyone have an ...
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126 views

Merge Sort implementation in Java

Can you check my merge sort implementation? From all of my testing it seems like it works, but I just wanted to make sure I am doing it as good as possible, and it couldn't be optimized any further. ...
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Is my implementation of a merge sort correct?

I tried to get into programming several times but never did and never got very far past "Hello, World.", until recently when I found and read (most of, still don't get parts of it) "The Little ...
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Implementation of merge sort and bubble sort

I'm new to Go and looking for a review of my merge sort and bubble sort implementations. What can be done better? Can my code be cleaner/clearer? ...
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Counting inversions

Inversion Count for an array indicates – how far (or close) the array is from being sorted. If array is already sorted then inversion count is 0. If array is sorted in reverse order that inversion ...
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Algorithm for finding inversions in Merge Sort

Please help in code reviews for readability, optimizing it, functionality etc. ...
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208 views

Merge Sort Java Implementation

Can someone check my Merge Sort implementation on Java? Is it good/bad and can it be improved further? ...
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567 views

Count array inversions merge sort

How does it look? Comments, code correctness, etc. ...
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151 views

Merge Sorting in Python

This my implementation of the Merge Sorting Algorithm: ...
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Merge sort algorithm implementation using C++ (redux)

This is a follow up question to the one I asked a couple of days ago. I reviewed the suggestions & did some research (specifically, read relevant info on CLRS). The new version is 3 times ...
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Merge sort algorithm implementation using C++

I'm trying to learn proper C++ and algorithms at the same time. I particularly feel weird about my iterators usage in merge function. Is this a good way to handle ...