import java.io.*;
import java.util.*;
import java.math.*;

class Main {
	
	public static void out (Object o) {
		System.out.println(o);
	}
	
	public static void main (String[] args) throws IOException {
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		BigDecimal n = new BigDecimal(br.readLine());
		
		out(n.multiply(BigDecimal.valueOf(1.08)));
		
	}
}