public class HelloWorld{
public static void main(String[] args){
for (int num = 999,count = 0;;count++)
if( num<=999999999&&num/=10)
{
while(num >= 0){
System.out.println("它是个"+ count+"位的数！");
}
}else{
System.out.println("输入有误！");
}
}
public class HellowWorld{
public static void main(String[] args){
int num = 999;
int count = 0;
if(num>=0 && num<=999999999){
for(int i=0 ;num !=i ; count++){
num = num/10;
}
System.out.println("它是个"+count+"位的数！");
}
}
}
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！");
}
}
}