#include <bits/stdc++.h>
using namespace std;
using ll=long long;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
#define all(x) x.begin(),x.end()
#define rep(i,j,n) for (long long i = j; i < (long long)(n); i++)
#define _GLIBCXX_DEBUG
const ll MOD = 1000000007;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
//(a+b-1)/b
//priority_queue<ll, vector<ll>, greater<ll>> q;


signed main(){
	//cout << fixed << setprecision(10);
	ll n,k; cin >> n >> k;
	if(n <= k){
		cout <<1 << endl;
		return 0;
	}
	if(n % k != 0 && n <= 2*k){
		cout << 3 << endl;
		return 0;
	}
	ll ans = 3;
	ll j = n /k +(n % k != 0);
	j -= 2;
	ans += j;
	cout << ans << endl;



	return 0;
}