#pragma GCC target("avx2") #pragma GCC optimize("03") #pragma GCC optimize("unroll-loops") #include using namespace std; typedef long double ld; typedef long long ll; typedef unsigned long long ull; #define endl "\n" #define FOR(i,a,b) for(int i=(a);i<=(b);i++) #define rep(i,n) for(int i=0;i<(n);i++) #define PII pair #define PLL pair #define ALL(x) (x).begin(), (x).end() constexpr int INF=1<<30; constexpr ll LINF=1LL<<60; constexpr ll mod=1e9+7; constexpr int NIL = -1; templateinline bool chmax(T &a, const T &b) { if (ainline bool chmin(T &a, const T &b) { if (binline int popcount(T a) {return __builtin_popcount(a);} templateinline T emod(T a, T p) { return (a%p + p) % p;} //------------------- int main() { cin.tie(0); ios::sync_with_stdio(false); //cout << fixed;//<< setprecision(15); ll n; cin >> n; string ans = ""; int cur = 1; rep(_, n) { cur *= 10; ans += '0' + (cur/7); cur -= (cur/7) * 7; } if(n==0) cout << "0" << endl; else { cout << "0." << ans << endl; } return 0; }