#include <iostream> //#include<atcoder/all> #include <numeric> #include <cmath> #include <limits> #include <stdio.h> #include <iomanip> #include <string> #include <vector> #include <algorithm> #include <utility> #include <tuple> #include <cstdint> #include <cstdio> #include <map> #include <queue> #include <set> #include <stack> #include <deque> #include <unordered_map> #include <unordered_set> #include <bitset> #include <cctype> //using namespace atcoder; using namespace std; using ll = long long; #define all(A) A.begin(),A.end() using vll = vector<ll>; #define rep(i, n) for (long long i = 0; i < (long long)(n); i++) using Graph = vector<vector<vector<pair<ll, ll>>>>; int main() { ll N; cin >> N; if (N <= 3) { cout << N << endl; } else cout << (N - 3) * 5 + 3 << endl; }