#include #ifdef _DEBUG #include "debug.hpp" #else #define debug(...) #endif #define fastIO (cin.tie(0), cout.tie(0), ios::sync_with_stdio(false)) #define rep(i, n) for (int i = 0; i < (n); ++i) #define precise(i) fixed << setprecision(i) using ill = int64_t; using ull = uint64_t; using namespace std; using std::cout; void solve() { int n; cin >> n; if (n % 2 == 0) cout << (1.5 * n) << '\n'; else cout << floor(n * 1.5) << '\n'; } void wrapper() { rep(i, 3) { cout << "[TEST " << i << "]\n"; solve(); cout << "\n"; } } int main() { fastIO; #ifdef _DEBUG wrapper(); #else solve(); #endif }