import java.io.PrintStream;
import java.util.Scanner;

public class WhileInput
{
   public static void main(String[] args)
   {
      PrintStream out = System.out;
      Scanner in = new Scanner(System.in);
      
      double sum = 0.0;
      out.print("Enter a real number: ");
      while (in.hasNext())
      {
         double value = Double.parseDouble(in.next());
         sum += value;
         out.print("Enter a real number: ");
      }
      out.println("\nSum of values: " + sum);
   }
}