#include<iostream>
#include<string>
#include<cstdio>
#include<cctype>
using namespace std;
int main(){
    int n,a[6]={1,4,2,8,5,7};
    cin>>n;
    if(n==0)cout<<0<<endl;
    else{
        cout<<"0.";
        for (int i=0; i<n; i++)cout<<a[i%6];
    }
    cout<<endl;
}