#include <iostream> #include <vector> #include <algorithm> #include <map> #include <queue> #include <cstdio> #include <ctime> #include <assert.h> #include <chrono> #include <random> #include <numeric> #include <set> using namespace std; typedef long long int ll; using ull = unsigned long long; int main(){ cin.tie(nullptr); ios::sync_with_stdio(false); int n; cin >> n; printf("%d\n",n+n%2 ); }