fn main() {
    let (n, _m) = {
        let mut line = String::new();
        std::io::stdin().read_line(&mut line).unwrap();
        let mut iter = line.split_whitespace();
        (
            iter.next().unwrap().parse::<usize>().unwrap(),
            iter.next().unwrap().parse::<usize>().unwrap(),
        )
    };
    let aa = {
        let mut line = String::new();
        std::io::stdin().read_line(&mut line).unwrap();
        line.split_whitespace()
            .map(|x| x.parse::<usize>().unwrap())
            .collect::<Vec<_>>()
    };

    let mut actual = vec![false; n + 1];
    for &a in aa.iter() {
        actual[a] = true;
    }

    let mut ans = 0_u32;
    let mut lockers = vec![false; n + 1];

    for i in 1..=n {
        if lockers[i] == actual[i] {
            ans += 1;
        } else {
            for j in (i..=n).step_by(i) {
                lockers[j] = !lockers[j];
            }
        }
    }

    println!("{}", ans);
}