import java.io.PrintStream;

public class Binary
{
   public static void main(String[] args)
   {
      PrintStream out = System.out;
      
      int value = Integer.parseInt(args[0]);
      
      int hundreds = value / 100;
      value = value % 100;
      int tens = value / 10;
      value = value % 10;
      int ones = value;
      
      int decimal = 4 * hundreds + 2 * tens + 1 * ones;
      out.println(decimal);
   }
}