#include <bits/stdc++.h>
using namespace std;
int r, a, b;
int main() {
  scanf("%d%d%d", &a, &b, &r);
  if (2 * r <= a && 2 * r <= b)
    cout << "First" << endl, exit(0);
  else
    cout << "Second" << endl, exit(0);
}
