#include <bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int,int> P;
int INF = 1e9+7;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
signed main() {
    int V,T,P;
    cin >> V >> T >> P;
    V+=P*V;
    cout << V+(V-1)/(T-1)+1 << endl;
}