#include <iostream> #include <cstdio> #include <numeric> #include <algorithm> #include <string> #include <vector> #include <functional> #include <cmath> #include <queue> #include <set> #define rep(i, a) FOR(i, 0, a) #define FOR(i, a, b) for(int i = a; i < b; ++i) typedef long long ll; typedef unsigned long long ull; typedef std::pair<int, int> P; typedef std::pair<P, int> PP; struct edge{ int to, time, cost; }; const double esp = 1e-9; const int max = (int)1e+5 + 10; int n; int main(){ std::cin >> n; if (n % 2 == 0)std::cout << n / 2 << std::endl; else std::cout << n << std::endl; return 0; }