public class Ex521 {
public static void main(String args[]){
if(args.length==1){
try{
double count=1.0;
double number=Double.parseDouble(args[0]);
System.out.println("number:"+args[0]);
while(Math.pow(10.0,count)<=number){
count++;
}
System.out.println("桁数は"+(int)count);

}
catch(NumberFormatException e){
System.out.println("引数には数字を入力");
}
}
else{
System.out.println("1つの引数に数字を入力");
}
}
}