quicksort

I have implemented a working quickSort algorithm using the first element in the array as the pivot, that look like this: public int[] quickSort( int[] a, int start, int end){ int l = start; int r = end; int pivotIndex = start; //<---- first element in the array as pivot! // must be at least two elements if ( end - start >= 1){ // set pivot int pivot = a[pivotIndex]; while ( r > l ){ // scan from the left while ( a[l] <= pivot && l <= end && r > l ){ l++; } while ( a[r] > pivot && r >= start && r >= l){ r--; } if ( r > l ){ this.swap(a, l, r); } } this.swap(a, pivotIndex, r); System.out.println

I want to modify QuickSort (in Java) so that every time Partition is called, the median of the proportioned array is used as the pivot. I have a median selection algorithm in Java that returns the kth smallest element, in this case the median. I have tons of quicksort algorithms in java that all work by themselves and sort an array. Unfortunately I can't combine those two in order to achieve the above... Everytime I try it i usually get stackoverflow erros. Can anybody show me code to see how it can be done? Thanks EDIT: For example this is a median selection algorithm that I have tried to use

I am working on analysis of sorting algorithms by plotting graphs in MATLAB. Below is my quick sort code. When I run it it is giving this error: Maximum recursion limit of 500 reached. Use set(0,'RecursionLimit', N) to change the limit. Be aware that exceeding your available stack space can crash MATLAB and/or your computer. Error in ==> quickSort Why does this error occur? Is there anything wrong in my code? function [ar] = quickSort(ar, low, high) if low < high [ar, q] = parti(ar, low, high); ar = quickSort(ar, low, q - 1); ar = quickSort(ar, q + 1, high); end end function [ar, i] = parti(ar

Approach 1 C.A.R Hoare introduced partitioning logic(shown below), which is taught in school, low = pivot = 0; i = 1; j = high = listSize-1; while (true) { while (a[i] <= a[pivot] && (i < high)) { i = i + 1; } while (a[j] >= a[pivot] && (j > low)) { j = j - 1; } if (i >= j) break; swap(a[i], a[j]) } swap(a[j], a[pivot]); // pivot element is positioned(once) return j; Approach 2 To basically try make it stable sort , Instead j pointing to last index( listSize-1 ), if j points to listSize/2 (i.e., mid ), then, we get into scenario where j > high or i >= mid , where a[i] do not have corresponding

This question already has an answer here: How to sort divs according to their id using jQuery? 3 answers I have this info in a variable "sortorder": "obj,exp,qual,edu,int,ref,img I also have corresponding div id's but in shuffled order. <div id = "qual">info</div> <div id = "exp">info</div> <div id = "edu">info</div> <div id = "int">info</div> <div id = "ref">info</div> <div id = "img">info</div> <div id = "obj">info</div> Now i have to sort the div's according to sortorder. The first should be obj, second should be exp like this <div id="obj">info<div> <div id="exp">info<div> <div id="qual"

I want to implement the QuickSort Algorithm on a sync Doubly Linked List. I give the function "partition" the left and right border, then it starts to search lower values on the left side and put the greater ones on the right side. This works because my pivot Element is alway the most rightern one and after this steps it is in the middle. I always get an endless loop and I dont know why? Maybe wrong abort condition? Her my code: private void quickSortRec(DoublyLinkedList in, ListElement l, ListElement r) { ListElement pivot = partition(in, l, r); if(pivot!=null && l!=r){ quickSortRec(in, in