Java正则表达式

import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Main 
{
    public static void main(String[] args) 
    {
        Scanner scanner = new Scanner(System.in);
        while(scanner.hasNext())
        {
            String input = scanner.next();
            String[] arr = input.split(";");
            String pattern = "[ADWS][0-9]{1,2}";
            Pattern r = Pattern.compile(pattern);
            List<String> list = new ArrayList<String>();
            for(int i=0;i<arr.length;i++)
            {
                Matcher m = r.matcher(arr[i]);
                // find()方法是部分匹配
                // matches()是全部匹配
                if(m.matches())
                {
                    list.add(m.group());
                }            
            }
            int x=0, y=0;
            for(int i=0;i<list.size();i++)
            {
                char direction = list.get(i).charAt(0);
                int len = Integer.valueOf(list.get(i).substring(1));
                //System.out.println(len);
                switch (direction)
                {
                case ‘A‘: x -= len;
                break;
                case ‘D‘: x += len;
                break;
                case ‘W‘: y += len;
                break;
                case ‘S‘: y -= len;
                break;
                default:
                    break;
                }
            }
            System.out.println(x+","+y);
        }    
        scanner.close();
    }

}