#include <bits/stdc++.h>   using namespace std;   const long long inf = 1e9;   const long long N = 1e5 + 10;   const long long bits = 30;   const long long mod = 1e9 + 7;   const long double pi = 3.14159265358979323846;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     ;     std::cout << std::fixed << std::setprecision(20);     ;     long double n;     cin >> n;     long double ans = 0;     for (long double i = 1; i <= n; i++) {       ans += (long double)1.0 / i;     }     cout << ans <<   n ;   }   