#include<cstdio>
#include <iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>

using namespace std;
typedef long long ll;
typedef pair<int, int> Pr;

ll N, M;

int main()
{
	cin >> N >> M;
	ll ans = N / M;
	ans /= 1000;
	ans *= 1000;
	cout <<  ans << endl;
	return 0;
}