#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

int main()
{
	int n;
	cin >> n;

	cout << 0;

	if(n == 0){
		cout << "\n";
		return 0;
	}

	cout << ".";
	
	for(int i = 0; i < n / 6; i++)
		cout << 142857;

	char loop[] = "142857";

	for(int i = 0; i < n % 6; i++)
		cout << loop[i];

	cout << "\n";
	
	return 0;
}