# Tag: quicksort

## How to fix StackOverflow error while using Quicksort for big arrays?

I’m doing a benchmark for different sorting and I’m getting a StackOverflowError using Quicksort for an array of size 100,000. I will also need to use Quicksort to sort an array of size 1,000,000 so I will get this problem again. I read about increasing the stack size but didn’t figure out how to do it properly. Answer To limit

## Index 16 out of bounds for length 16

I am trying to sort an array of x elements using quickSort but I am getting an error “Index 16 out of bounds for length 16” please help. Answer For an array of 16 elements the indexes are 0 to 15. Thus index 16 is not part of the array and you get the OutOfBoundsException.

## Java Quick Sort Performance

I was doing sorting array problems and found one of the quick sorting solution extremely fast, and the only difference is the two lines of code in function 1Partition. Wondering why the following two lines of code in 1Partition can greatly improve the performance: Here’s the full source code: } Answer I guess you are doing the question on a

## Doubly Linked List QuickSort Implementation Problem

I’ve implemented a classic Doubly Linked List: class Node { protected T data; protected Node next, prev; } class DoublyLinkedList> { …

## QuickSort descending order

I am trying to implement QuickSort in a descending order. I have tried to trace through my code to see why it is only partially-sorted. My input was an int array of: {3,4,6,1,9,7}. After sorting, I got {9,4,7,6,3,1}, where 4 is not in the correct place. Answer Your code should look something like this:

## Stackoverflow with Quicksort Java implementation

Having some problems implementing quicksort in java. I get a stackoverflow error when I run this program and I’m not exactly sure why. If anyone can point out the error, it would be great. si is the starting index. ei is the ending index. Answer First you should fix the bounds of the qsort recursive call as suggested by Keith,

## Why does QuickSort use O(log(n)) extra space?

I have implemented the below quicksort algorithm. Online I’ve read that it has a space requirement of O(log(n)). Why is this the case? I’m not creating any extra data structures. Is it because my recursion will use some extra space on the stack? If this is the case, is it possible to do it with less memory by not having

## Quick Sort Sorts Descending Not Ascending

I just implemented QuickSort algorithm from book and got weird output. It works but it sorts in descending order instead of ascending. For example: [1, 5, 2, 10, 6, 9, 8, 3, 7, 4] is sorted [10, 9, 8, 7, 6, 5, 4, 3, 2, 1] cant seem to find source in my code: INITIAL CALL: how do i calculate