using System;

public class Program

{

    public static void Main()

    {

        int i,f1=-1,f2=1,f3,n=5;

        Console.WriteLine("fibonacci series");

    for(i=1;i<=n;i++)

        {

            f3=f1+f2;

            f1=f2;

            f2=f3;

        Console.WriteLine(f3);

        }

    }

}