expr2.java

旅行商问题 某售货员要到若干城市去推销商品

import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import java.math.*;
public class expr2 extends Applet{
	int i,n=20,r=200;
	String s=new String("123");
	int path[]={1,14,6,18,9,7,13,15,11,17,3,5,12,4,2,8,19,16,10,20};
	double a[][]=new double[21][2];
	public void paint(Graphics g){
	for(i=1;i<=n;i++){
		a[i][0]=r*(1+Math.cos(i*360.0/n))+100;
		a[i][1]=r*(1+Math.sin(i*360.0/n))+150;
		s=Integer.toString(i);
		g.drawString(s,(int)(a[i][0]),(int)(a[i][1]));
		g.setColor(Color.red);
		g.fillOval((int)(a[i][0])-2,(int)(a[i][1])-2,10,10);
		System.out.println((int)a[i][0]+" "+(int)a[i][1]);

		}
		g.setColor(Color.blue);
		g.fillOval((int)a[1][0]-1,(int)a[1][1]-1,10,10);

		g.setColor(Color.black);
	for(i=0;i<n-1;i++){
		g.drawLine((int)a[path[i]][0],(int)a[path[i]][1],(int)a[path[i+1]][0],(int)a[path[i+1]][1]);
	}

	}
}