#include #define For(i, a, b) for(int i = a; i < b; i++) #define rep(i, n) For(i, 0, n) #define rFor(i, a, b) for(int i = a; i >= b; i--) #define ALL(v) (v).begin(), (v).end() #define rALL(v) (v).rbegin(), (v).rend() using namespace std; using lint = long long; using ld = long double; int INF = 2000000000; lint LINF = 1000000000000000000; int main() { lint n, m; cin >> n >> m; lint ans = n / m / 1000LL * 1000LL; cout << ans << endl; }