题解 | #表示数字#

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 str = in.nextLine();
        char[] chars = str.toCharArray();
        StringBuilder sb = new StringBuilder();
        boolean preIsNumber = false;
        for(char c : chars) {
            if(c >= '0' && c <= '9') {
                if(preIsNumber) {
                    sb.append(c);
                } else {
                    sb.append("*");
                    sb.append(c);
                }
                preIsNumber = true;
            } else {
                if(preIsNumber) {
                    sb.append("*");
                }
                sb.append(c);
                preIsNumber = false;
            }
        }
        if(preIsNumber) {
            sb.append("*");
        }
        System.out.println(sb.toString());
    }
}