#include <algorithm>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <functional>
#include <iostream>
#include <map>
#include <memory>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <vector>

using namespace std;

typedef long long ll;

#define sz size()
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(c) (c).begin(), (c).end()
#define rep(i,a,b) for(ll i=(a);i<(b);++i)
#define per(i,a,b) for(ll i=(b-1);i>=(a);--i)
#define clr(a, b) memset((a), (b) ,sizeof(a))
#define ctos(c) string(1,c)
#define print(x) cout<<#x<<" = "<<x<<endl;

#define INF 3000000000000000000LL

int main() {
  long long a,b,c;
  cin>>a>>b>>c;

  if(a>1000000000000000000LL)return 0;
  if(b>1000000000000000000LL)return 0;
  if(c>1000000000000000000LL)return 0;

  long long low = 1;
  long long high = 1000000000000000000LL;
  while(low < high){
    long long mid = (high + low) >> 1;
    long long d2 = mid / a;
    long long d1 = mid - d2;
  
    if(d2 > (INF - d1) / b || d1 + d2 * b >= c){
      high = mid;
    }
    else{
      low = mid + 1;
    }
  }
  cout << low << endl;
  return 0;
}