#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
  #include "settings/debug.cpp"
  #define _GLIBCXX_DEBUG
#else
  #define Debug(...) void(0)
#endif
using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); ++i)

int main() {
  ll h, a;
  cin >> h >> a;
  ll ans = 0, cnt = 1;
  while (h > 0) {
    ans += cnt;
    cnt *= 2;
    h /= a;
  }
  cout << ans << endl;
  return 0;
}