#include <bits/stdc++.h>
using namespace std;
long long MOD = 1000000007;
long long pw(long long a, long long b) {
  long long r = 1;
  while (b > 0) {
    if (b & 1) {
      r = (r * a) % MOD;
    }
    b = b >> 1;
    a = (a * a) % MOD;
  }
  return r;
}
int main() {
  int a, b, r;
  cin >> a >> b >> r;
  int n = 1;
  int row = 0, col = 0;
  if (a >= 2 * r) {
    row = (a / (2 * r));
  }
  if (b >= 2 * r) {
    col = (b / (2 * r));
  }
  if ((row * col) == 0) {
    cout << "Second\n";
  } else
    cout << "First\n";
  return 0;
}
