#include<bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

  int a,b,c; cin >> a >> b >> c;

  function< int(int) > check =
  [&](int mid){
    return (unsigned long long)(mid/a * b) + (mid - mid/a) >= c;
  };

  int ok = c;
  int ng = -1;
  while(abs(ok-ng) > 1){
    int mid = (ok + ng) / 2;
    if(check(mid)) ok = mid;
    else ng = mid;
  }
  cout << ok << endl;

  return 0;
}