#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:25600000")
using namespace std;
const double pi = acos(-1.0);
const double eps = 1e-9;
const int INF = 1000000000;
int main() {
  int a, b, r;
  cin >> a >> b >> r;
  cout << (min(a, b) >= 2 * r ? "First\n" : "Second\n");
}
