#include <bits/stdc++.h>
typedef long long ll;
using namespace std;

const int INF = 1e9;
const int MOD = 1e9+7;
const ll LINF = 1e18;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) for(int i=0;i<(n);++i)
#define REPR(i,n) for(int i=n;i>=0;i--)
#define ALL(v) (v.begin(),v.end())
#define COUT(x) cout<<(x)<<'\n'


int main(){
    int n;
    cin >> n;
    vector<int> vec={1,4,2,8,5,7};
    if(n==0)COUT(0);
    else{
        cout << "0.";
        REP(i,n){
            cout << vec[i%6];
        }
        cout << endl;
    }
    return 0;
}