Java 代码

import java.util.Scanner;

public class Main
{   
    public static double add(double x, double y)
    {
        return x + y;
    }

    public static void main(String[] args)
    {
        Scanner cin = new Scanner(System.in);

        double m = cin.nextDouble();
        double n = cin.nextDouble();

        System.out.println (String.format("%.2f", add (m, n)));
    }
}