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// Author: Bartek Knapik

#include <cstdio>
#include <unordered_set>
#include <unordered_map>
#include <vector>

using namespace std;

int n, q, s;
unordered_set<int> stones;

const int MAX_N = 10000000+9;
vector<bool> is_prime(MAX_N, true);
vector<int> primes;
int counter[MAX_N];


int answer(int max_n)
{
    int res, d, p;

    d = stones.size();
    if (d < 3)
        return d;
    
    res = d / 2;
    for (int i = 0; res * primes[i] <= max_n; ++i)
    {
        p = primes[i];
        for (int j = 0; j < p; ++j)
            counter[j] = 0;
        for (int stone: stones)
        {
            int pos = stone % p;
            counter[pos]++;
            if (counter[pos] > res)
                res = counter[pos];
        }
    }
    return res;
}


int main()
{
    int max_n;
    is_prime[0] = is_prime[1] = false;
    for (int i = 2; i * i <= MAX_N; i++)
        if (is_prime[i])
            for (int j = i * i; j <= MAX_N; j += i)
                is_prime[j] = false;
    
    for (int i = 2; i <= MAX_N; ++i)
        if (is_prime[i])
            primes.push_back(i);

    scanf("%d%d", &n, &q);
    stones.clear();
    max_n = 0;
    for (int i = 0; i < q; ++i)
    {
        scanf("%d", &s);
        max_n = max_n < s ? s : max_n;
        if (stones.count(s))
            stones.erase(s);
        else
            stones.insert(s);
        printf("%d\n", answer(max_n));
    }
    return 0;
}