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#include <iostream>
#include <vector>
#include <unordered_set>

using namespace std;

typedef long long int LL;

const int MAX_N = 10000005;

int n, q, a;

bool sieve[MAX_N];
vector<int> primes;
unordered_set<int> stones;
int rems[MAX_N];

void findPrimes()
{
	sieve[0] = sieve[1] = 1;

	for (int x = 2; x < MAX_N; ++x)
	{
		if (!sieve[x] && LL(x) * LL(x) <= LL(MAX_N))
		{
			for (int y = x * x; y < MAX_N; y += x)
			{
				sieve[y] = true;
			}
		}
	}

	for (int i = 2; i < MAX_N; ++i)
	{
		if (!sieve[i])
		{
			primes.push_back(i);
		}
	}
}

int solve()
{
	if (stones.empty())
	{
		return 0;
	}

	int res = 0;

	for (int p : primes)
	{
		if (p > 2 * n / stones.size())
		{
			break;
		}

		unordered_set<int> toClean;
		for (int s : stones)
		{
			int rem = s % p;
			++rems[rem];

			if (rems[rem] > res)
			{
				res = rems[rem];
			}

			toClean.insert(rem);
		}
		for (int r : toClean)
		{
			rems[r] = 0;
		}
	}

	return res;
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(NULL);

	findPrimes();

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

		if (stones.find(a) != stones.end())
		{
			stones.erase(a);
		} 
		else
		{
			stones.insert(a);
		}

		cout << solve() << endl;
	}
	
	return 0;
}