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

class Process {
    private long D;

    Process(long D) {
        this.D = D;
    }

    BigDecimal getResult() {
        var result = new BigDecimal("0");
        
        // *1.08
        result = (new BigDecimal(D)).multiply((new BigDecimal("1.08")));
        
        return result;
    }
}

public class Main {
    public static void main(String[] args) throws IOException {
        var bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        var printWriter    = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

        // 入力
        long D = Long.parseLong(bufferedReader.readLine().trim());

        // 処理および出力
        printWriter.println((new Process(D)).getResult());
        
        bufferedReader.close();
        printWriter.close();
    }
}