[algorithm] Why is quicksort better than mergesort?

Actually, QuickSort is O(n2). Its average case running time is O(nlog(n)), but its worst-case is O(n2), which occurs when you run it on a list that contains few unique items. Randomization takes O(n). Of course, this doesn't change its worst case, it just prevents a malicious user from making your sort take a long time.

QuickSort is more popular because it:

  1. Is in-place (MergeSort requires extra memory linear to number of elements to be sorted).
  2. Has a small hidden constant.

Examples related to algorithm

How can I tell if an algorithm is efficient? Find the smallest positive integer that does not occur in a given sequence Efficiently getting all divisors of a given number Peak signal detection in realtime timeseries data What is the optimal algorithm for the game 2048? How can I sort a std::map first by value, then by key? Finding square root without using sqrt function? Fastest way to flatten / un-flatten nested JSON objects Mergesort with Python Find common substring between two strings

Examples related to sorting

Sort Array of object by object field in Angular 6 Sorting a list with stream.sorted() in Java How to sort dates from Oldest to Newest in Excel? how to sort pandas dataframe from one column Reverse a comparator in Java 8 Find the unique values in a column and then sort them pandas groupby sort within groups pandas groupby sort descending order Efficiently sorting a numpy array in descending order? Swift: Sort array of objects alphabetically

Examples related to language-agnostic

IOException: The process cannot access the file 'file path' because it is being used by another process Peak signal detection in realtime timeseries data Match linebreaks - \n or \r\n? Simple way to understand Encapsulation and Abstraction How can I pair socks from a pile efficiently? How do I determine whether my calculation of pi is accurate? What is ADT? (Abstract Data Type) How to explain callbacks in plain english? How are they different from calling one function from another function? Ukkonen's suffix tree algorithm in plain English Private vs Protected - Visibility Good-Practice Concern

Examples related to quicksort

Quicksort with Python Quicksort: Choosing the pivot Why is quicksort better than mergesort?

Examples related to mergesort

Mergesort with Python How to merge two sorted arrays into a sorted array? How to sort in-place using the merge sort algorithm? Why is quicksort better than mergesort?