CALCULATING FIBONACCI NUMBER USING GOLDEN RATIO

import java.io.*;

class Main

{

     static double goldenRatio=(1+Math.sqrt(5))/2;

          

     public static void main(String args[])throws IOException

     {

           BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

           System.out.println(fibonacci(Integer.parseInt(br.readLine())));

     }

     public static int fibonacci(int n)

     {

           return (int)((Math.pow(goldenRatio,n)/Math.pow(5,0.5))+0.5);

     }

}