#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#define REP(i,n) for(int i=0;i<(n);++i)
#define SORT(a) sort((a).begin(),(a).end())
#define PB push_back
using namespace std;
typedef vector<int> VI;
typedef queue<int> QI;

int main(){
  long long int N, M;
  cin >> N >> M;
  cout << N / (M*1000) * 1000 << endl;
}