import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.util.*;

public class Try2 {

    public static void main(String[] args)
    {
        DecimalFormatSymbols s = new DecimalFormatSymbols();
        s.setDecimalSeparator('.');
        DecimalFormat f = new DecimalFormat("#,####0.0000",s);
        Scanner in = new Scanner(System.in);
        while (in.hasNextLong())
        {
        System.out.println(f.format(Math.sqrt(in.nextLong()) ));
        }
    }
}