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Member Avatar for Reverend Jim

##vbScript - Sorting With and Without Code Please see my post [vbScript - The Basics](https://www.daniweb.com/programming/threads/516400/vbscript-the-basics) for more details on vbScript. Sorting is something that must be done from time to time. I'm going to examine three ways. The first is the well known (at least by name) QuickSort method. Rather …

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Member Avatar for Reverend Jim

Over the years I've seen a lot of discussion (and several implementations) of the Quicksort algorithm. Most of what I have seen, unfortunately, lacks sufficient commenting as well as meaningful variable names. Hopefully the following vbScript code will more clearly show how Quicksort actually works. A couple of incidental notes: …

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Member Avatar for inspire_all

Hello everyone,i think i know quick sort algorithm.But i need help in figuring out its worst case. Lets look at the below quicksort code----> void quicksort(int arr[],int low,int high) //low and high are pased from main() { int m; if(low<high) { m=partition(arr,low,high); quicksort(arr,low,m-1); quicksort(arr,m+1,high); } } int partition(int arr[],int low,int …

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Member Avatar for Griff0527

I am trying to write several different sorting algorithms in order to time the differences between them when reading a file of a half million integers. For testing purposes, I am only using a few hundred integers, but I am getting a stack overflow error. Also, for testing reasons, I …

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Member Avatar for HankReardon

Hello, What is the best way to count the number of swaps required to sort an array that is sorted using the Quicksort algorithm? I put a counter in what I believe is in the correct position and the tests that I have run seem to be correct however Quicksort …

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Member Avatar for MachDelta

Hi everyone. I've been struggling with a quicksort implementation here. I think - scratch that - I know i'm overrunning an array (erm, vector) based on how it explodes, but I honestly can't see it and I have no debugger. I slept on it but fresh eyes didn't get me …

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Member Avatar for shibu2all

void quick_sort (int *a, int n) { if (n < 2) return; int p = a[n / 2]; int *l = a; int *r = a + n - 1; while (l <= r) { while (*l < p) l++; while (*r > p) r--; if (l <= r) { …

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Member Avatar for Sasstraliss

Quickselect, based on quicksort, and counting select, based on counting sort. Each is capable of finding the kth smallest element in an unsorted/sorted list/array. This is some example code for a QuickSelect algorithm. This doesn't include the partition function. // return the kth smallest item int quickSelect(int items[], int first, …

Member Avatar for mike_2000_17
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Member Avatar for t_daniweb

Having trouble getting the QuickSort to work in this code. I turned off the counter for now, just trying to get the sorted array to display correctly. This is the results I get from the code: This program keeps track of the number of comparisons required to to sort a …

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Member Avatar for aditdano

I have a problem with this code : [CODE] #include<iostream> using namespace std; void qsort(int A[], int len) { if(len>=2){ int l=0; int u=len-1; int pivot=A[rand()%len]; while(l<u) { while(A[l]<pivot)l++; while(A[u]>pivot)u--; swap(A[l], A[u]); } qsort(A,l); qsort(&A[l+1],len-l-1); } else{return;} } void swap(int a, int b) { int temp; temp=a; a=b; b=temp; } …

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Member Avatar for challarao

Hi.... I wrote a program for Quick Sort algorithm.... It is compiled fine....but it is giving a run time error i.e., Segmentation Fault.... I tried hard but couldn't find out what is that thing causing segmentation error in this program.... Please help.... I'm getting segmentation fault very frequently (i'm using …

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Member Avatar for fox196

Hi, I'm getting segmentation fault errors when I use quicksort with ~350 000+ numbers. This is the quick sort algorithm I'm using: [CODE]void swap(int* v, int i, int j) { int tmp = v[i]; v[i] = v[j]; v[j] = tmp; } int partition(int *v, int s, int e) { int …

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Member Avatar for George_91

I've this quicksort code, and it compiles. The thing is, I don't know how to give random values (integers) to the vector. The program should ask for the vector's size and then create the x random integers so it can apply the quiksort method. [CODE]#include "stdafx.h" #include <iostream> #include <vector> …

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Member Avatar for rarment

I keep getting a stackOverflow error in my quickSort and I can not figure out why. Any help would be greatly appreciated!! [CODE] private static void quickSortRecPriv(int[] arr, int first, int last, int ps) { int pivot = arr[first]; int left = first; int right = last; if (arr == …

Member Avatar for JamesCherrill
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Member Avatar for mushahidh

CONVERT THIS QUICK SORT PROGRAM INTO PARTITION OF 3,5,7OR 11 ELEMENTS. [CODE] #include"stdafx.h" #include<iostream> using namespace std; #include <stdio.h> #include <stdlib.h> #define size 50 void swap(int *x,int *y) { int temp; temp = *x; *x = *y; *y = temp; } int partition(int i,int j ) { return((i+j) /2); } …

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Member Avatar for vineeth vs

pls any one tell me why the loop is not ending?? (program for quick sort)[CODE][/CODE] [CODE]#include<stdio.h> int partition(int a[],int l,int r); void quicksort(int a[],int low,int high); int loc,temp,pivot,a[50],low,high,left,right; int main() { int n,i; printf("\nEnter the no: of elements : " ); scanf("%d",&n); printf("\nEnter the numbers : "); for(i=0;i<n;i++) { printf(" …

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Member Avatar for Thendi

Hi I am trying to put quicksort in my class like other methods and call it using the main method, I did it for Selection, Insertion, Bubble Sort and I need one more which is quicksort. I already made the calling code for quicksort but I don't know how to …

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Member Avatar for Lelly

Hello, Can anybody explain to me how can I do: Implement the Random partitioning version of Quicksort. Take care that your data array is not copied (by value) into your subroutines, because you will sort the RandomEnglishDictionary.txt file. Report the first, 1000th and last elements in your sorted list. Thanks

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Member Avatar for EneilShade

I was humming along, and decided to try out data sorting. So, I did a few pieces of research, and came up with a really cool looking algorithm: Quicksort. I did what I should have, and started to program. Now, here is where I sound like an idiot: Why is …

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Member Avatar for Narue

This quicksort implements the basic recursive algorithm with three improvements. The first improvement is choosing the pivot based on the median of three values in the list to be sorted. This minimizes the chances of a worst case scenario. The second improvement speeds up the algorithm by termination when subfiles …

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The End.