public void quicksort(int[] d, int lo, int hi){
	if(lo<hi){
		int pivotIndex=partition(d, lo, hi);
		quicksort(d,lo,pivotIndex-1);
		quicksort(d,pivotIndex+1,hi);
		}
	public int partition(int[] d,int lo, int hi){
		intStack smaller = new intStack();
		intStack larger = new intStack();
		int pivot = d[hi];
		for(int i=lo;i<hi;i++){
			if(d[i]<pivot)
				smaller.push(d[i]);
			else
				larger.push(d[i]);
		}
		int i=lo;
		while(!smaller.isEmpty()){
			d[i]=smaller.pop();
			i++;
		}
		d[i] = pivot;
		int pivotIndex = i;
		i++;
		while(!larger.isEmpty()){
			d[i] = larger.pop();
			i++;
		}
	return pivotIndex;
	}
}