求教到底哪写错了
public class HelloWorld{ public static void main(String[] args){ int num = 999; int count = 0; if(num>=0 && num<=999999999){ while(num!=0){ count++; num/=10; } System.out.println("它是个"+count+"位的数!"); }else{ System.out.println("输入有误!");} } 求教到底哪里错了啊???谢谢