import java.math.BigInteger; import java.util.Arrays; import java.util.Scanner; class Main { public static void main(String[] args) throws Exception { new Main().run(); } void run() { Scanner sc=new Scanner(System.in); int N=sc.nextInt(); BigInteger a=BigInteger.valueOf(10).pow(N); a=a.divide(BigInteger.valueOf(7)); System.out.println("0."+a); } static void tr(Object... objects) { System.out.println(Arrays.deepToString(objects)); } }