algorithm - Understanding quicksort - Stack Overflow algorithm quicksort(A, lo, hi) is if lo < hi then p := partition(A, lo, hi) quicksort(A, lo, p – 1) quicksort(A, p + 1, hi) Hoare partition scheme Uses two indices that start at the ends of the array being partitioned, then move toward each other, until they detect an inversion: a pair of elements, one greater than the pivot, one smaller
algorithm - Quick Sort Vs Merge Sort - Stack Overflow Quicksort is usually faster than this, but given the theoretical worst possible input, it could run in O(n^2), which is worse than the worst possible merge sort Quicksort is also more complicated than mergesort, especially if you want to write a really solid implementation, and so if you're aiming for simplicity and maintainability, merge sort
Why is quicksort better than mergesort? - Stack Overflow Quicksort has a better average case complexity but in some applications it is the wrong choice Quicksort is vulnerable to denial of service attacks If an attacker can choose the input to be sorted, he can easily construct a set that takes the worst case time complexity of o(n^2)
sorting - VBA array sort function? - Stack Overflow '_2023_11_22 Function fArraySort(Optional arr_Sort As Variant, Optional lngLBound As Long, Optional lngUBound As Long) As Variant Static arrSort() As Variant 'store copy of array for sorting Dim lstSort As Object 'arraylist Dim varKey As Variant 'convert array to arraylist Dim varPivot As Variant 'quicksort pivot Dim lngLeftIndex As Long
algorithm - How is quicksort related to cache? - Stack Overflow What makes quicksort a good algorithm is that on real computers, not all memory accesses take the same time The main memory, SDRAM has a latency that seems very long from the CPU's point of view (typically hundreds of CPU cycles)
Why bubble sort is faster than quick sort - Stack Overflow Quicksort: nlog(n) Bubblesort: n^2 So based on this, Quicksort is faster than Bubblesort However, Quicksort handles degenerate cases poorly When the list is in almost-sorted order already, Quicksort is going to keep recursing Bubblesort will stop as soon as its done, making Bubblesort faster in such cases
algorithm - Quicksort: Iterative or Recursive - Stack Overflow I learnt about quicksort and how it can be implemented in both Recursive and Iterative method In Iterative method: Push the range (0 n) into the stack; Partition the given array with a pivot; Pop the top element Push the partitions (index range) onto a stack if the range has more than one element; Do the above 3 steps, till the stack is empty
algorithm - How to optimize quicksort - Stack Overflow The quicksort ALREADY performs a comparison of the pivot with every element being sorted, so adding a comparison for equality adds no cost Once you have partitioned the elements in two sets and if you know that you have "many" values equal to the pivot then ONLY a second pass just to process the values that are equal to the pivot