public class HelloWorld{
public static void main(String[] args){
int num = 222;
int count = 0;
if((0<=num)&&(num<=9)){
System.out.println("它是1位的数");}
if((10<=num)&&(num<=99)){
System.out.println("它是2位的数");}
if((100<=num)&&(num<=999)){
System.out.println("它是个3位的数!");}