题解 | #表示数字#

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        char[] arr = str.toCharArray();
        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < arr.length; i++) {
            if (Character.isDigit(arr[i]) == false) {
                sb.append(arr[i]);
            } else {
                if (i == 0 || Character.isDigit(arr[i - 1]) == false) {
                    sb.append("*" + arr[i]);
                } else {
                    sb.append(arr[i]);
                }

                if (i == arr.length - 1 || Character.isDigit(arr[i + 1]) == false) {
                    sb.append("*");
                }
            }
        }

        System.out.println(sb.toString());



    }

}