?int count=0; ?

? Scanner sum=new Scanner(System.in);

? System.out.println("請輸入一個整數");

? int sum1=sum.nextInt();

? if(sum1>=0){

while(sum1!=0){

count++;

sum1/=sum1;

}

System.out.println("是個"+count+"位的數");

? }else{

? System.out.println("輸入有誤");

? }