#include <bits/stdc++.h>
using namespace std;
void solve() {
  int a, b, r;
  cin >> a >> b >> r;
  if (min(a, b) < (2 * r))
    cout << "Second" << endl;
  else
    cout << "First" << endl;
}
int main() {
  int t;
  t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
