fn main() {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();
	let mut n: Vec<u64> = s.split_whitespace().flat_map(str::parse).collect();
	(2..=n[2]).for_each(|_| (n[0], n[1]) = (n[1], n[0] ^ n[1]));
	println!("{}", n[1.min(n[2] as usize)])
}