use std::{collections::HashMap, io::Read};

fn main() {
	let mut s = String::new();
	std::io::stdin().read_to_string(&mut s).ok();
	let mut h = HashMap::new();
	s.split_whitespace()
		.skip(1)
		.flat_map(str::parse::<u32>)
		.for_each(|a| *h.entry(a).or_insert(0) += 1);
	println!("{}", h.iter().filter(|(_, &v)| v == 1).count());
}