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#include <bits/stdc++.h>

using namespace std;
#define fors(u, n, s) for(int u = (s); u<(n); u++)
#define foru(u, n) fors(u, n, 0)
#define f first
#define s second
#define vec vector
#define pb push_back
#define sz(x) ((int)x.size())
typedef long long ll;
typedef long double db;

#define div div69

// #define debug(x) cerr << __LINE__ << " | " << x << endl
#define debug(x) {}

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx2")

const int N = 1e7+100;
int mn_prime[N];

const int S = 64;
__int128 barrett[N];

void init_barrett(__int128 b){
	__int128 bg = ((__int128)1LL)<<S;

	barrett[b] = bg/b + (bg%b != 0);
}

int div(__int128 a, int b){
	// cerr << a << " " << b << endl;
	if(barrett[b] == 0) init_barrett(b);

	// cerr << a*barrett[b] << endl;
	// cerr << ((a*barrett[b])>>S) << endl;

	assert((a*barrett[b])>>S == a/b);

	return (a*barrett[b])>>S;
}

int mod(int a, int b){
	return a - div(a, b)*b;
}

void init_primes(){
	foru(i, N) mn_prime[i] = -1;

	fors(i, N, 2){
		if(mn_prime[i] != -1) continue;

		for(int j = i; j < N; j += i)
			if(mn_prime[j] == -1)
				mn_prime[j] = i;
	}
}

void factors(int x, vec<int> &out){
	while(x != 1){
		int p = mn_prime[x];
		out.pb(p);

		while(true){
			int nxt = div(x, p);
			if(nxt*p != x) break;
			x = nxt;
		}
		// while(x%p == 0) x /= p;
	}

// 	int idx = 0;
// 	while(primes[idx]*primes[idx] <= x){
// 		if(x%primes[idx] == 0) out.pb(primes[idx]);
// 		while(true){
// 			int next_x = x/primes[idx];
// 			if(next_x*primes[idx] != x) break;
// 			x = next_x;
// 		}
// 		idx++;
// 	}
// 
// 	if(x != 1) out.pb(x);
}

const int SL = 75;
mt19937 mt{};

db rnd_db(){
	return (db)mt()/(db)UINT_MAX;
}

vec<int> st;
map<int, int> idx_map;

struct Edge{
	int from;
	int to;
	int cnt;	
};

map<pair<int, int>, int> edges_cnt;
vec<pair<int, int>> v_edges;

struct prime{
	int pr;
	int rem;
	int cnt;
	int val;	

	prime(int a, int b, int c, int d) : pr(a), rem(b), cnt(c), val(d) {}
};

vec<prime> primes_vec;

void delta(int x, int del){
	for(auto &i : primes_vec) {
		if(mod(x, i.pr) == i.rem) i.val += del;
	}
}

	int rnd(){
		return st[mt()%sz(st)];
	}

void add_prime(int p, int r){
	int idx = 0;
	while(idx != sz(primes_vec) && (primes_vec[idx].pr != p || primes_vec[idx].rem != r)) 
		idx++;
		
	if(idx == sz(primes_vec)){
		primes_vec.pb(prime(p, r, 1, 0));
		for(auto i : st) if(mod(i, p) == r) primes_vec.back().val++;
	}else{
		primes_vec[idx].cnt++;
	}
}

void rem_prime(int p, int r){
	int idx = 0;
	while(idx != sz(primes_vec) && (primes_vec[idx].pr != p || primes_vec[idx].rem != r)) 
		idx++;

	primes_vec[idx].cnt--;

	if(primes_vec[idx].cnt == 0){
		swap(primes_vec[idx], primes_vec.back());
		primes_vec.pop_back();
	}
}

	void add_edge(pair<int, int> edge){
		vec<int> p;
		factors(edge.s-edge.f, p);

		for(auto i : p) {
			debug("adding " << i << " from edge " << edge.f);
			debug("mod " << mod(edge.f, i));
			add_prime(i, mod(edge.f, i));
		}
	}

	void rem_edge(pair<int, int> edge){
		vec<int> p;
		factors(edge.s-edge.f, p);

		for(auto i : p) rem_prime(i, mod(edge.f, i));
	}

	void add_num(int x){
		delta(x, 1);

		if(sz(st) <= 1){
			return;
		}
	
		db p = (db)(2*sz(st)-1)/((db)sz(st)*(db)sz(st));

		int cnt = 0;
		foru(_i, SL) if(rnd_db() <= p) cnt++;

		if(sz(v_edges) == 0){
			cnt = SL;
			goto skip;
		}

		foru(_i, cnt){
			int idx = mt()%sz(v_edges);

			pair<int, int> edge = v_edges[idx];
			swap(v_edges[idx], v_edges.back());
			v_edges.pop_back();

			edges_cnt[edge] --;
			if(edges_cnt[edge] == 0)
				edges_cnt.erase(edge),
				rem_edge(edge);
		}

		skip:;

		foru(_i, cnt) {
			int y = rnd();
			while(y == x){
				y = rnd();
			}

			pair<int, int> edge = {min(x, y), max(x, y)};

			v_edges.pb(edge);

			if(edges_cnt[edge] == 0) add_edge(edge);
			edges_cnt[edge]++;
		}
	}

	void rem_num(int x){
		delta(x, -1);
	
		vec<int> to_delete;
		foru(i, sz(v_edges)) if(v_edges[i].f == x || v_edges[i].s == x) to_delete.pb(i);
		reverse(to_delete.begin(), to_delete.end());

		for(auto i : to_delete){
			pair<int, int> edge = v_edges[i];
			swap(v_edges[i], v_edges.back());
			v_edges.pop_back();

			edges_cnt[edge]--;
			if(edges_cnt[edge] == 0)
				edges_cnt.erase(edge),
				rem_edge(edge);
		}

		if(sz(st) <= 1){
			assert(sz(v_edges) == 0);
			assert(sz(edges_cnt) == 0);
			return;
		}

		foru(_i, sz(to_delete)) {
			int a = rnd();
			int b = rnd();
			while(a == b) b = rnd();

			pair<int, int> edge = {min(a, b), max(a, b)};
			v_edges.pb(edge);

			if(edges_cnt[edge] == 0)
				add_edge(edge);
			edges_cnt[edge] ++;
		}

	}

	void handle(int x){
		auto pt = idx_map.find(x);
		
		if(pt == idx_map.end()){
			idx_map[x] = sz(st);
			st.pb(x);
			add_num(x);
		} else {
			int idx = pt->s;
			swap(st[idx], st.back());
			st.pop_back();

			if(idx < sz(st)) idx_map[st[idx]] = idx;
			idx_map.erase(x);

			rem_num(x);
		}
	}

int get_ans(){
	if(sz(st) == 0) return 0;
	int ans = 1;
	for(auto i : primes_vec) ans = max(ans, i.val);

	return ans;
}

void solve() {

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

	foru(_i, q){
		int x; cin >> x;

		handle(x);

		cout << get_ans() << endl;
	}
	
}

int main()
{
	cin.tie(0); cout.tie(0);
	ios_base::sync_with_stdio(0);

	srand(time(NULL));

	init_primes();

	solve();

	return 0;
}