追问能不能把代码直接贴出来
追答import java.text.NumberFormat;
import java.util.Scanner;
public class Main {
private static int getNum(int i) {
System.out.println(i%10);
return i/10;
}
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);//控制台(用户)输入
System.out.println("请输入圆的半径:");
double r=scanner.nextDouble();
double per=2*Math.PI*r;
double area=3.14159*r*r;
NumberFormat nf = NumberFormat.getNumberInstance();//NumberFormat及保存小数的方法
nf.setMaximumFractionDigits(2);
System.out.println("周长为:"+(nf.format(per)));
System.out.println("面积为:"+(nf.format(area)));
Scanner sc=new Scanner(System.in);//控制台(用户)输入
System.out.println("请输入一个3位的整数:");
int i = sc.nextInt();
if(i>99 && i<1000){
while(true){
i = getNum(i);
if(i==0){
break;
}
}
}
}
}