#include <iostream> #include <vector> #include <map> #include <set> #include <queue> #include <string> #include <iomanip> #include <algorithm> #include <cmath> #include <stdio.h> using namespace std; #define int long long int MOD = 1000000007; signed main() { cin.tie(0); ios::sync_with_stdio(false); int N; cin >> N; cout << fixed << setprecision(15) << 1.0 / N << endl; }