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#include <iostream>
#include <vector>
#include <algorithm>
#include <bitset>

using namespace std;

struct SparseSet
{
    vector<int> dense, sparse;

    SparseSet(int capacity) : sparse(capacity + 1) {}

    bool contains(int x) const
    {
        if (x < 0 || x >= sparse.size())
            return false;
        int index = sparse[x];
        return index < dense.size() && dense[index] == x;
    }

    void insert(int x)
    {
        if (contains(x))
            return;

        sparse[x] = dense.size();
        dense.push_back(x);
    }

    void remove(int x)
    {
        if (!contains(x))
            return;

        int index_to_remove = sparse[x];
        int last_val = dense.back();

        dense[index_to_remove] = last_val;
        sparse[last_val] = index_to_remove;

        dense.pop_back();
    }

    void toggle(int x)
    {
        if (contains(x))
        {
            remove(x);
        }
        else
        {
            insert(x);
        }
    }

    size_t size() const { return dense.size(); }
    auto begin() const { return dense.begin(); }
    auto end() const { return dense.end(); }
};

vector<int> get_primes(int limit)
{
    vector<int> primes;
    static bitset<10000005> is_prime;
    is_prime.set();
    is_prime[0] = is_prime[1] = 0;

    for (int p = 2; p * p <= limit; p++)
    {
        if (is_prime[p])
        {
            for (int i = p * p; i <= limit; i += p)
                is_prime[i] = 0;
        }
    }

    for (int p = 2; p <= limit; p++)
    {
        if (is_prime[p])
            primes.push_back(p);
    }
    return primes;
}

int solve(const SparseSet &stoneIndices, vector<int> &count, int k)
{
    int maxValue = -1;

    for (const auto s : stoneIndices)
    {
        int rem = s % k;
        count[rem]++;
        maxValue = max(maxValue, count[rem]);
    }

    for (const auto s : stoneIndices)
    {
        count[s % k] = 0;
    }

    return maxValue;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

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

    int a;

    SparseSet stoneIndices(n);
    auto primes = get_primes(10000005);
    vector<int> count(n + 1);

    for (int i = 0; i < q; i++)
    {
        cin >> a;
        stoneIndices.toggle(a);
        int baseline = solve(stoneIndices, count, 2);
        int limit = n / baseline;
        int result = baseline;
        int current = 3;
        int idx = 2;

        while (current <= limit)
        {
            result = max(result, solve(stoneIndices, count, current));
            current = primes[idx];
            idx++;
        }

        cout << max(0, max(baseline, result)) << endl;
    }

    return 0;
}