/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		System.out.println(getSeries(50));
	}
	
	
	static ArrayList<Double> getSeries(int n)
	{
		ArrayList<Double> series = new ArrayList<>();
        		series.add(0.0); // This is working as replacement of the F(0)
        		series.add(1.0); // This is working as replacement of the F(1)
        		double x, y;
        		
        		for (int i = 1; i < n; i++)
        		{
            	    x = series.get(i - 1); // This is working as replacement of the F(n-2)
            	    y = series.get(i); // This is working as replacement of the F(n-1)
            	    series.add(x + y);
        		}
		        
        		return series;
    	}
    
    
}