/* package whatever; // don't place package name! */
 
/* The class name doesn't have to be Main, as long as the class is not public. */
class Main
{
  public static void main (String[] args) throws java.lang.Exception
  {
     String i1 = "12345678";
     String i2 = "3";
     double d1 = Double.parseDouble(i1);
     double d2 = Double.parseDouble(i2);
     double d = d1 + d2;
     System.out.println( String.format("%f", d) ); 
  }
}