#include<bits/stdc++.h>

using namespace std;

using int64 = long long;

int main()
{
  int64 A, B, C;
  cin >> A >> B >> C;

  int64 low = 0, high = 1LL << 62;
  while(high - low > 1) {
    auto mid = (low + high) / 2;
    auto money = mid / A * B + mid - mid / A;
    if(money >= C) high = mid;
    else low = mid;
  }

  cout << high << endl;

  return (0);
}