import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;

public class No0285 {
	
	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br= new BufferedReader(new InputStreamReader(System.in));
		long D = Long.parseLong(br.readLine());
		BigDecimal price = new BigDecimal(D);
		BigDecimal tax = new BigDecimal("1.08");
		price = price.multiply(tax);
		
		System.out.println(price);
	}
}