Quicksort

public class QuickSort {

 public static void main(String[] args) {
  
  QuickSort obj = new QuickSort();
  int[] a = new int[] {3,5,2,7,6,1};
//  int[] a = new int[] {1,2,10,4,5};
  obj.quickSort(a, 0, a.length-1);
  //System.out.println("sorted array ==" + a.toString());
  
 }
 
 public void swap(int[] a, int index1, int index2){
  
  int temp = a[index1];
  a[index1] = a[index2];
  a[index2] = temp;
 }
 
 public int partition(int[] a, int low, int high){
  
  int pivot = a[high];
  int m = low;
  
  for(int i=low; i <= high-1; i++){
   if(a[i] < pivot){
    //put all elements less than pivot to the left of pivot 
    swap(a, i, m);
    m++;
   } 
  }
  swap(a, m, high); 
  return m;
 }
 
 public void quickSort(int[] a, int low, int high){
  
  if(low < high){
   int pivot = partition(a, low, high);
   quickSort(a, low, pivot-1);
   quickSort(a, pivot+1, high);
  }
 }

}