#include <iostream>
using namespace std;
int nya[4] = {1,4,2,8};
int main(){
    int n;cin>>n;
    cout << 0;
    if(n){
        cout << ".";
        for(int i = 0; n > i; i++){
            cout << nya[i%4];
        }
    }
    cout << endl;
    
}