#include <bits/stdc++.h>
using namespace std;

void fast_io() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
}

int main() {
	fast_io();
	long long h, a;
	cin >> h >> a;
	long long ans = 0, cnt = 1;
	while (h) {
		ans += cnt;
		h /= a;
		cnt *= 2;
	}
	cout << ans << "\n";
}