#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, e) for (int i = (int)(s); i < (int)(e); ++i)

int main() {
	cin.tie(nullptr);
	ios_base::sync_with_stdio(false);
	
	ll H, A;
	cin >> H >> A;
	
	ll ans = 0;
	ll t = 1;
	while (H > 0) {
		ans += t;
		H /= A;
		t <<= 1;
	}
	cout << ans << '\n';
}