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use std::collections::HashSet;

macro_rules! input {
    (from $iter:expr, $($r:tt)*) => {
        input_inner!{$iter, $($r)*}
    };
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        let s = {
            use std::io::Read;
            let mut s = String::new();
            std::io::stdin().read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

fn get_primes(n: usize) -> Vec<usize> {
    let mut primes = Vec::new();
    let mut is_prime = vec![true; n + 1];

    for i in 2..=n {
        if is_prime[i] {
            primes.push(i);

            for j in (i * i..=n).step_by(i) {
                is_prime[j] = false;
            }
        }
    }

    primes
}

fn count_for_k(stones: &HashSet<usize>, k: usize) -> usize {
    let mut reminders = vec![0; k];

    for stone in stones {
        reminders[stone % k] += 1;
    }

    reminders.iter().max().copied().unwrap_or(0)
}

fn main() {
    input! {
        n: usize,
        q: usize,
        a: [usize; q],
    }

    let primes = get_primes(n);
    let mut stones = HashSet::new();

    for a in a {
        if !stones.remove(&a) {
            stones.insert(a);
        }

        if stones.len() < 3 {
            println!("{}", stones.len());
            continue;
        }

        let limit = 2 * n / stones.len() + 1;

        let results = primes
            .iter()
            .take_while(|&&p| p <= limit)
            .map(|&p| count_for_k(&stones, p))
            .collect::<Vec<_>>();

        // eprintln!("{:?}", results);
        println!("{}", results.iter().max().unwrap());
    }
}