#include<iostream>
#include<iomanip>
#include<cmath>
#include<string>
#include<vector>
#include<list>
#include<algorithm>
#include<map>
#include<set>
#include<queue>
#include<stack>
using namespace std;
typedef long long ll;
#define fi first
#define se second
#define mp make_pair
#define rep(i, n) for(int i=0;i<n;++i)
#define rrep(i, n) for(int i=n;i>=0;--i)
const int inf=1e9+7;
const ll mod=1e9+7;
const ll big=1e18;
const double PI=2*asin(1);

int main() {
  ll V, T, P;
  cin>>V>>T>>P;
  ll ans = V*P+V;
  ll num = (ans-1)/T+1;
  ans += num;
  while((ans-1)/T+1>num) {
    ans++;
    num++;
  }
  cout<<ans<<endl;
}