#pragma GCC target("avx")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
using namespace std;
#define rep(i, n) for (long long i = 0; i < (long long)(n); i++)
using ll = long long;
using P = pair<ll,ll>;

int main(){
ios::sync_with_stdio(false);
std::cin.tie(nullptr);
ll v,t,p;
cin >> v >> t >> p;
cout << (p + 1) * v + ((p + 1) * v - 1) / (t - 1) + 1 << endl;
}