#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class T> using vec = vector<T>;
template <class T> using vvec = vector<vec<T>>;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    ll V,T,P;
    cin >> V >> T >> P;
    ll now = V*(P+1);
    ll ans = 1;
    while(now>=T){
        ll t = now/T;
        ans += t;
        now %= T;
        now += t;
    }
    ans += V*(P+1);
    cout << ans << "\n";
}