Java回文数.如"12321","123454321"(5个数)

代码:

import java.util.Scanner;
//回文数.如"12321","123454321"(5个数)
public class _04 {
   
    public static void main(String[] args) {
   
        Scanner sc =new Scanner(System.in);
        System.out.println("请输入一个数");
        int a=sc.nextInt();
        String s=" ";
        for(int o=1;o<=a;o++){
   
            s=s+o+" ";
        }
        for (int o=a-1;o>0;o--){
   
            s=s+o+" ";
        }
        System.out.println(s);
    }
}

输出: