void QuickSort(int *arr, int maxlen, int begin, int end)  
{  
    int i, j;  
    if (begin < end) {  
        i = begin + 1;  
        j = end;        
        while (i < j) {  
            if(arr[i] > arr[begin]) {  
                swap(&arr[i], &arr[j]); 
                j--;  
            } else {  
                i++; 
            }  
        }  
        if (arr[i] >= arr[begin]) {  
            i--;  
        }  
        swap(&arr[begin], &arr[i]);      
        QuickSort(arr, maxlen, begin, i);  
        QuickSort(arr, maxlen, j, end);  
    }  
}  
 
void swap(int *a, int *b)    
{  
    int temp;  
    temp = *a;  
    *a = *b;  
    *b = temp;  
}