#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
using ll = long long ;
using P = pair<int,int> ;
using pll = pair<long long,long long>;
constexpr int INF = 1e9;
constexpr long long LINF = 1e17;
constexpr int MOD = 1000000007;
constexpr double PI = 3.14159265358979323846;

int main(){
    ll v,t,p;
    cin >> v >> t >> p;

    ll all = v*(p+1) - 1;
    if(all==0){
        cout << 2 << endl;
        return 0;
    }

    ll ans = 1 + (all/t)*(t+1);
    ++ ans;
    ans += (all%t) + 1;

    cout << ans << endl;

    return 0;
}