（笑）什么意思？判断一个素数能被几个9整除

package CompileProject;
/*判断一个素数能被几个9整除 
 *
 *
 * 意义何在？
 *
 * */
import java.util.Scanner;

public class P30 {
    
    public int input() {
        System.out.println("请输入一个素数");
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();
        return num;
    }

    /**
     *
     * 方法描述：判断是否是素数
     * @param num
     * @return
     */
    public boolean sushu(int num) {
        boolean b = true;
        for (int i = 2; i < num; i++) {
            if (num % i == 0) {
                b = false;
                break;
            }
        }
        return b;
    }

     /**
     * 判断输入是否合法，计算素数能被几个九整除
     *
     * @return
     */
    public void suan(int num) {
        int count = 0;
        int temp = num;
        if (sushu(num)) {
            System.out.println("你输入的素数是" + num);
        } else {
            System.out.println("输入不合法，请重新开始");
            return;
        }
        int count2 = 0;
        while (true) {
            count2++;
            if (temp % 9 == 0) {
                count++;
                temp /= 9;
            } else {
                if (count2 == 1) {
                    System.out.println("素数" + num + "不能被9整除");
                } else {
                    System.out.println("素数" + num + "能被" + count + "个9整除");
                }
                break;
            }
        }
    }

    public static void main(String[] args) {
        P30 p = new P30();
        int num = p.input();
        p.suan(num);
    }
}