这样写不对吗？
public class HelloWorld{
public static void main(String[] args){
int num = 999;
int count = 0;
if ((num >= 0)&&(num <= 1000000000)){
for(;num < 10;count++){
for(;num < 10;){
num = num/10;
}
}
}
System.out.println("它是个"+count+"位的数！");
}
}
