题解 | 坐标移动

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String s = in.nextLine();
        String[] split = s.split(";");
        int x = 0;
        int y = 0;
        for (String s1 : split) {
            //先判断指令是否合法
            if (isValid(s1)) {
                String substring = s1.substring(0, 1);
                String substring1 = s1.substring(1);
                if ("A".equals(substring)) {
                    x -= Integer.parseInt(substring1);
                }
                if ("D".equals(substring)) {
                    x += Integer.parseInt(substring1);
                }
                if ("W".equals(substring)) {
                    y += Integer.parseInt(substring1);
                }
                if ("S".equals(substring)) {
                    y -= Integer.parseInt(substring1);
                }
            }
        }
        System.out.println(x + "," + y);
    }

    public static boolean isValid(String s) {
        char[] charArray = s.toCharArray();
        if (charArray.length < 2) {
            return false;
        }
        if (charArray.length >= 4) {
            return false;
        }
        if (charArray[0] == 'A' || charArray[0] == 'S'
                || charArray[0] == 'D' || charArray[0] == 'W') {
            for (int i = 1; i < charArray.length; i++) {
                if (charArray[i] < '0' || charArray[i] > '9') {
                    return false;
                }
            }
        }
        return true;
    }
}