Quicksort program in c using recursion

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Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. C program for quicksort recursive Ask Question. Asked 6 years, 7 months ago. Active 6 years, 7 months ago. Viewed times. Improve this question. Koosh Doctor Koosh Doctor 27 2 2 silver badges 4 4 bronze badges.

General suggestion: Don't ask user input for the array size when you already have a fixed size array. It may go rogue. The following C program, using recursion, performs quick sort. A quick sort is a sorting algorithm with complexity of O nlogn.

It is used for sorting numbers, structure, files. Here is the source code of the C Program to implement Quick Sort using recursion. The C Program is successfully compiled and run on a Windows system. The program output is also shown below. Above is the source code for C Program to implement Quick Sort using recursion which is successfully compiled and run on Windows System.

This partitions the array into two parts-left partition and right partition. The same method is applied for each of the partition. The process continues till no more partition can be made. We shall be considering the first element as the pivot element.

The recursive function is similar to Mergesort seen earlier. However, in quick sort, we do not divide into two equal parts but partition on the basis of the pivot element. The function sorts elements a[lb] to a[ub] where lb stands for lower bound and ub stands for the upper bound. Now we must write the function to partition the array.

We shall choose the first element of the sub-array as the pivot and find its correct position in the sub-array. We will be using two variables i. We use two pointers up and down initialized to the first and last elements respectively. If up and down cross each other i.