Quick Sort (java)

[int Array기반 간단한 QuickSort]
- http://www.algolist.net/Algorithms/Sorting/Quicksort  참고. 
=>c++ 코드 참조하면.. 한번소트 후에, 끝나면 i가 j보다 크군요..
 (j=2, i=3) 이때, j포함 왼쪽.  i포함 오른쪽 돌려야 함.
	
	public void quickSort(int arr[], int left, int right) {
	      int i = left, j = right;
	      int tmp;
	      int pivotValue = arr[(left + right) / 2];
	 
	      /* partition */
	      while (i <= j) {
	            while (arr[i] < pivotValue)
	                  i++;
	            while (arr[j] > pivotValue)
	                  j--;
	            if (i <= j) {
	                  tmp = arr[i];
	                  arr[i] = arr[j];
	                  arr[j] = tmp;
	                  i++;
	                  j--;
	            }
	      };
	 
	      /* recursion */
	      if (left < j)
	            quickSort(arr, left, j);
	      if (i < right)
	            quickSort(arr, i, right);
	}
	
	public static void main(String args[]){
	
		SortSearch s = new SortSearch();
		
		int A[] = new int[] {9,8,7,6,5,4,3,2,1};
		s.quickSort(A, 0, A.length-1);
		
		for (int a : A){
			System.out.println(a);
		}
         }



-----------아래 건은 연습용------------------ 
[Simple Quick Sort Example.. with String Array]
  - using End element as a temporary Pivot.

 
public class QuickSort {


    void swap(String data[], int i, int j){
        String tmp = data[i];
        data[i]=data[j];
        data[j]=tmp;
    }

    public void qSort( String[] data, int st, int end){
        if (st == end || end < 0) return;
        
        String pivot=data[end];  //Pivot is End (temporary)

        int j=end-1;
        int i=0;
        while (i<j) {
            while ( i<j && data[i].compareTo(pivot) < 0 ) i++;
            while ( j>i && data[j].compareTo(pivot) > 0) j--;
            if (i < j)
                swap(data, i, j);
        };

        System.out.println( "new Pivot:" +i + ","+j);
        
        //IF pivot Largest ?
        if ( j == end-1 && data[j].compareTo(pivot) < 0 )  // (j == end-1) =>sometimes wrong. when only 3 data.
            qSort(data, 0, end-1);
            
        //General pivot
        else {
            swap(data, i ,end);  //i is real Pivot
            qSort(data, 0,   i-1); //left divide and conquer:recursive
            qSort(data, j+1, end); //right divide and comquer:recursive
        }
    }

    /////////main
    public static String datas[]={"adf", "kk", "bb", "aa", "dd", "cc", "ff" };
    public static void main(String args[]){
        QuickSort q = new QuickSort();
        q.qSort(datas, 0, datas.length-1);

        for( String a : datas)
            System.out.println(a);
    }
}