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#include <algorithm>
#include <cmath>
#include <iostream>
#include <vector>

using namespace std;
using LL = long long;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, q, a;
    cin >> n >> q;

    vector<int> primes;
    vector<bool> tmp(n);

    for (int i = 2; i < (n + 1) / 2; i++)
    {
        if (!tmp[i])
        {
            primes.push_back(i);

            for (int j = i + i; j < n; j += i)
            {
                tmp[j] = true;
            }
        }
    }

    if (primes.size() == 0)
        primes.push_back(2);

    vector<bool> stones(n + 1);
    vector<int> stonesInd(n + 1);
    vector<int> stonesPos;
    vector<int> mods(n + 10);
    vector<int> used(n + 10);

    for (int t = 0; t < q; ++t)
    {
        cin >> a;

        if (stones[a])
        {
            int ind = stonesInd[a];

            stonesPos[ind] = stonesPos.back();
            stonesInd[stonesPos[ind]] = ind;
            stonesPos.pop_back();
        }
        else
        {
            stonesInd[a] = stonesPos.size();
            stonesPos.push_back(a);
        }

        stones[a] = !stones[a];

        if (stonesPos.size() < 2)
        {
            cout << stonesPos.size() << "\n";
            continue;
        }
        else if (stonesPos.size() == 2)
        {
            cout << (abs(stonesPos[0] - stonesPos[1] == 1) ? 1 : 2) << "\n";
            continue;
        }

        int res = (stonesPos.size() + 1) / 2;

        for (int i = 0; i < primes.size(); ++i)
        {
            int prime = primes[i];

            if ((LL)res * prime > n)
                break;

            int mx = 0;
            int ucnt = 0;

            for (int i = 0; i < stonesPos.size(); ++i)
            {
                int m = stonesPos[i] % prime;

                mx = max(mx, ++mods[m]);

                if (mods[m] == 1)
                    used[ucnt++] = m;

                if (mx + stonesPos.size() - 1 - i <= res)
                    break;
            }

            for (int i = 0; i < ucnt; ++i)
            {
                mods[used[i]] = 0;
            }

            res = max(res, mx);
        }

        cout << res << "\n";
    }

    return 0;
}