杭电 2003 ( 求绝对值 ) java

import java.util.Scanner;import java.text.DecimalFormat;public class Main {    public static void main(String[] args) {        Scanner sc = new Scanner(System.in);        while (sc.hasNext()) {            double num = sc.nextDouble();            DecimalFormat df2 = new DecimalFormat("##.00");            System.out.println(df2.format(Math.abs(num)));        }    }}