#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, r, t, t1;
  cin >> a >> b >> r;
  if (r + r > a) {
    cout << "Second";
    return 0;
  }
  if (r + r > b) {
    cout << "Second";
    return 0;
  }
  cout << "First";
}
