Quick Sort


refer

Code:

package sorting_algorithms;

import java.util.Arrays;

public class QuickSort {

    static void quickSort(int[] a, int p, int r){

        if(p<r){

            int pivot = partition(a, p, r);
            quickSort(a, p, pivot -1);
            quickSort(a, pivot+1, r);

        }


    }

    static int partition(int[] a,int p,int r){

        int pivotelem = a[r];
        int i = p-1;

        for(int j= p; j<r; j++){

            if(a[j] < pivotelem){
                i++;

                int temp = a[i];
                a[i] = a[j];
                a[j] = temp;
            }
        }

        int temp = a[i+1];
        a[i+1] = a[r];
        a[r] = temp;

        return i+1;
       
    }

    public static void main(String args[])
    {
        int arr[] = {12, 11, 13, 5, 6, 7};

        System.out.println("Given Array");
        System.out.println(Arrays.toString(arr));

        quickSort(arr, 0, arr.length-1);

        System.out.println("\nSorted array");
        System.out.println(Arrays.toString(arr));
    }

}


Output:

Given Array
[12, 11, 13, 5, 6, 7]

Sorted array
[5, 6, 7, 11, 12, 13]



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