#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <tuple>
#include <cstdint>
#include <cstdio>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <deque>
#include <unordered_map>
#include <unordered_set>
#include <bitset>
#include <cctype>
#include <random>
#include <cassert>
#include <numeric>
#define ll long long int
#define LL unsigned long long
#define pb push_back
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,n) for(int i=1;i<=(n);i++)
using namespace std;

int mx8[] = {0,0,1,-1,-1,1,-1,1};
int my8[] = {-1,1,0,0,-1,-1,1,1};
int mx4[] = {1,-1,0,0};
int my4[] = {0,0,-1,1};
const int MOD = 1000000007;



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

    ll f = (v + p * v + 1 / t) / (t - 1);
    ll l = v - f * t + f + 1 / t + p * v;
    cout << f * t + 1 + l << endl;


}