错在哪里了？
import java.util.Scanner;
public class HelloWorld{
public static void main(String[] args){
int num;
int count=0;
Scanner s=new Scanner(System.in);
num=s.nextInt();
if(num>=0&&num<1000000000){
while(num!=0){
count++;
num=num/10;
}
System.out.println("它是个"+count+"位的数！");
}else
System.out.println("输入错误");
}
}
