import java.awt.*;
import java.applet.*;

public class QSDemo extends Applet implements Runnable {

	static class Quicksort {

		static void qsort(int items[]) {
			qs(items,0,items.length-1);
			}

		static void qs(int items[],int left, int right){
			int i, j;
			int x, y;
	
			i = left; j = right;
			x = items[left];
	
			do {
				while((items[i] < x) && (i < right)) i++;
				while((x < items[j]) && (j > left)) j--;
	
				if(i <= j) {
					y = items[i];
					items[i] = items[j];
					items[j] = y;
					i++; j--;
					}
				} while( i<= j);


	
			if(left < j) qs(items, left, j);
			if(i < right) qs(items, i, right);
			}
		}

	int stuff[] = new int[100];
	int a,b,c,q;
	boolean start=true;
	public void init(){
		setBackground(Color.white); 
		}

	public boolean mouseDown (Event e, int x, int y) {
		if(!start) start=true;
		return true; 
		}

	public void start(){
		Thread t = new Thread(this);
		t.start();
		}

	public void paint(Graphics g){
		for(a=0;a<100;a++){
			g.setColor(Color.green);
			g.fillRect(0,a,stuff[a],1);
			}
		}

	public void run() {
		while(true){
			if(start){
				for(int i=0;i<stuff.length;i++)
					stuff[i]=(int)(Math.random()*100);

				repaint();
				try{Thread.sleep(100);}
				catch(InterruptedException e){}	
		
				Quicksort.qsort(stuff);
				start=false;
		
				repaint();
				try{Thread.sleep(100);}
				catch(InterruptedException e){}			

				}
			}
		}
	}