#include <iostream>

int main() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);

  int64_t diplomas_count;
  int64_t width;
  int64_t height;
  std::cin >> width >> height >> diplomas_count;

  int64_t left = 0;
  int64_t right = std::max(width, height) * diplomas_count;
  while (left + 1 < right) {
    int64_t mid = left + (right - left) / 2;
    if ((double(mid / width) * double(mid / height)) < diplomas_count) {
      left = mid;
    } else {
      right = mid;
    }
  }

  std::cout << right;

  return 0;
}