public class Fib1
{
  public static long evenSum(int k)
  {
    while(k % 3 != 0)
      k--;
    long sum = Fib.fib(k+2) - 1;
    return sum / 2;
  }

  public static void main(String args[])
  {
    if(args.length != 1)
    {
      System.err.println("Usage: java Fib1 <k>");
      System.exit(1);
    }
    int k = Integer.parseInt(args[0]);
    System.out.println("The sum of the even fib numbers =" + evenSum(k));
  }
}