#include <iostream> #include <cstring> #include <vector> #include <set> #include <list> #include <map> #include <deque> #include <algorithm> #include <utility> using namespace std; typedef long long ll; typedef unsigned long long ull; typedef vector<ll> vll; typedef vector<vector<ll>> vvll; #define for1(i,n) for (ll i=0;i<(n);i++) #define for2(i,m,n) for (ll i=(m);i<(n);i++) #define for3(i,m,n,d) for (ll i=(m);i<(n);i+=(d)) #define DEBUG 0 template <class T> void dumplist(T list) { for (auto item : list) { cout << item << " "; } cout << endl; } void solve() { ll N; cin >> N; N *= 1.5; cout << N << endl; } int main() { do { solve(); } while (DEBUG); }