#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, r;
  cin >> a >> b >> r;
  int at = a;
  r *= 2;
  bool first = false;
  bool second = true;
  while (b - r >= 0) {
    while (a - r >= 0) {
      if (first) {
        first = false;
        second = true;
      }
      if (second) {
        first = true;
        second = false;
      }
      a -= r;
    }
    a = at;
    b -= r;
  }
  if (first) cout << "First" << endl;
  if (second) cout << "Second" << endl;
}
