#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
#define rep(i,s,e) for(int (i) = (s);(i) <= (e);(i)++)

int main(){
  i64 A,B,C;
  cin >> A >> B >> C;
  i64 l = 0;
  i64 r = 1e18 + 1;
  function<i64(i64)> f = [&](i64 k){
    return (k / A) * B + (k - k / A);
  };
  while(r - l > 1){
    i64 mid = (r + l) / 2;
    if(f(mid) >= C){
      r = mid;
    }
    else{
      l = mid;
    }
  }
  cout << r << endl;
}