//QuickSort Main
package qs;
import java.util.*;

public class main {

	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		System.out.println("Imput num of elements");
		int N = input.nextInt();
		int[] ARR = new int[N];
		 for (int i = 0; i < N; i++) {
			 System.out.printf("Input[%d] elements:" , i);
			 ARR [i] = input.nextInt();
		 }
		 System.out.printf("BEFORE SORT" + Arrays.toString(ARR));
         quicksort.QuickSortMethods.QuickSort(ARR,0,n-1);
        System.out.println("After sorting : " + Arrays.toString(ARR));
		 }
	}
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//QuickSortMethods
package qs;

public class methods {

	public static void QuickSort(int[] ARR,int low, int high ) {
		if(low < high) {
			int PivotIndex = Partition(ARR, low, high);
			QuickSort(ARR, low, PivotIndex-1);
			QuickSort(ARR, PivotIndex+1, high);
		}
	}

	private static int Partition(int[] aRR, int low, int high) {
		//
		int Pivot = aRR[high];
		int  i = low-1;
		for(int j = low; j < high; j++) {
			if(aRR[j] < Pivot);
			i++;
			//swap
			int temp = aRR[j];
			aRR[j] = aRR[i];
			aRR[i] = temp;
		}
	//слагаме pivot елемента на правилното място
		int temp = aRR[i+1];
		aRR[i+1] = aRR[high];
		aRR[high] = temp;
		return i + 1;
	}
}