#include <bits/stdc++.h>

using namespace std;
using ll = long long;

ll H, A;

map<ll, ll> mp;
ll f(ll X){
    if (X <= 0) return 0;
    if (mp.count(X)) return mp[X];
    return f(X/A)*2 + 1;
}

int main(){

    cin >> H >> A;
    cout << f(H) << endl;

    return 0;
}