#include <iostream>

using namespace std;
int main(void){
    long long A,B,C;
    cin >> A >> B >> C;  
    long long low = 1;
    long long high = 1000000000000000000;
  
    while(low < high)
    {
    long long mid = (high + low) >> 1;
    long long block = mid / A;
    long long Anum = mid - block;
  
    if(Anum + block * B >= C)
    {
      high = mid;
    }
    else
    {
      low = mid + 1;
    }
  }
  cout << low << endl;
}