#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
typedef long long ll;
typedef pair<ll,ll> P;
//typedef modint998244353 mint;
int a[6]={1,4,2,8,5,7};
int main(void){
    cin.tie(0);
    ios::sync_with_stdio(0);
    int n;
    cin>>n;
    if(n==0){
        cout<<0<<endl;
    }else{
        cout<<"0.";
        for(int i=0;i<n;i++){
            cout<<a[i%6];
        }
        cout<<endl;
    }

}