#include <bits/stdc++.h>
using namespace std;
long long const MX = 2e5;
long long const INF = 1e18;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long a, b, r;
  cin >> a >> b >> r;
  if (a < 2 * r || b < 2 * r)
    cout << "Second";
  else
    cout << "First";
  return 0;
}
