#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <queue>
#include <cstdio>
#include <ctime>
#include <assert.h>
#include <chrono>
#include <random>
#include <numeric>
#include <set>
using namespace std;
typedef long long int ll;
using ull = unsigned long long;

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    ll v,t,p; cin >> v >> t >> p;
    ll res=(p+1)*v;
    ll now=res;
    while(1){
        res+=now/t;
        if(now/t==0)break;
        now=now%t+now/t;
    }
    if(now)res++;
    cout << res << endl;
}