qs java

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

/**
 * Created by MOHIT on 10-09-2017.
 */

 // Program to implement quick sort in java
public class quick_sort{
    public static void main(String arg[]){

        // accepting string as comma seperated inputs
        String input_string;
        ArrayList<Integer> myList1 = new ArrayList<Integer>();
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter the Array to be Sorted : ");
        input_string = sc.next();
        String[] temp = input_string.split(",");

        // adding those integers to array list
        for (String t:temp) {
            myList1.add(Integer.parseInt(t));
        }

        // print the list
        System.out.println("The list before sorting is : ")
        for (int temp2:myList1) {
            System.out.print(temp2 + "\t");
        }

        // calling the quick sort function with first position as 0 and last position as list size -1
        myList1 = Quick_Sort(myList1, 0, myList1.size()-1);

        // printing the sorted list
        System.out.println("\nThe Sorted List is : ");
        // displaying the sorted list
        for (int temp2:myList1) {
            System.out.print(temp2 + "\t");
        }
    }

    // recursive function to implement quick sort
    static ArrayList<Integer> Quick_Sort(ArrayList<Integer> data, int first, int last)
    {
        int pivot, left_mark, right_mark;

        // checking if the list has more than one number
        if(first < last)
        {
            // initialise variables
            pivot = first;
            left_mark = first;
            right_mark = last;

            // loop while left marker is less than right marker
            while(left_mark < right_mark)
            {
                // while the data at the left mark is less than pivot keep incrementing the left_mark
                while(data.get(left_mark) <= data.get(pivot) && left_mark < right_mark)
                    left_mark++;

                // while the data at the right mark is greater than pivot keep decrementing the right_mark
                while(data.get(right_mark) >= data.get(pivot) && left_mark <= right_mark)
                    right_mark--;

                // swap the elements if right mark is greater than left mark
                if(right_mark > left_mark)
                {
                    Collections.swap(data, left_mark, right_mark);
                }

                // finally swap the pivot and the right mark element
                Collections.swap(data, pivot, right_mark);
            }

            // make recursive calls to the function
            Quick_Sort(data, first, right_mark-1);
            Quick_Sort(data, right_mark+1, last);
        }

        // returning the sorted list
        return data;
    }

}