#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007LL;
const double PI = 2 * acos(0);
int main(void) {
  std::ios_base::sync_with_stdio(false);
  int a, b, r;
  cin >> a >> b >> r;
  if (a < 2 * r || b < 2 * r)
    cout << "Second";
  else
    cout << "First";
  return 0;
}
