hdu_2003 求绝对值

import java.text.DecimalFormat;import java.util.Scanner;/** * Created by Administrator on 2017/11/12. */public class Main {    public static void main(String[] args){        Scanner scan = new Scanner(System.in);        while (scan.hasNext()){            double r    = scan.nextDouble();            DecimalFormat df = new DecimalFormat("#0.00");            System.out.println(df.format(Math.abs(r)));        }    }}