Aqui muestro la forma de sumar dos numeros introducidos por el usuario

import java.io.*;
public class suma
{
    public static void main (String [] args)
    {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader (isr);

        try
        {
            System.out.print("Numero 1 : ");
            int s1 = Integer.parseInt(br.readLine());
            System.out.print("Numero 2 : ");
            int s2 = Integer.parseInt(br.readLine());
            int suma=s1+s2;
            System.out.println ("La suma es " + s1 + "+" + s2 +"="+ suma);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }
}

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