哪位帮我看看哪出错了
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("它是位"+count+"个位数!");
}else{
System.out.println("输出有误!");
}
}
}
