HDU 2003 求绝对值

import java.util.Arrays;
import java.util.Scanner;

public class Main{
//    public final static double pi = 3.1415927;
    public static void main(String[] args) {
        
        Scanner sin=new Scanner(System.in);
        while(sin.hasNextDouble()){
            double num = sin.nextDouble();
            num = Math.abs(num);
            String res = String.format("%.2f", num);
            System.out.println(res);
        }
    }
}