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#include <bits/stdc++.h>
using namespace std;

typedef long long int lli;
const int MAXN = 10000015;

const int D = 19;  // TODO adjust if necessaty

int prime[MAXN];
vector<int> prf[MAXN];

int pcnt[MAXN];
int used[MAXN];
int is_repr[MAXN]; // loc at repr vector + 1
int unused_loc[MAXN]; // loc at unused vector + 1

vector<int> primes;
int p_id[MAXN];

vector<int> unused;  // unused values
vector<int> repr;  // representants
vector<int> diffs_v[D+5];  // for each representant for each prime how many active elements are there?
vector<int> diffs_k[D+5];

int inc_diffs(int r, int p) {
	if (diffs_v[r][p_id[p]] == 0)
		diffs_k[r].push_back(p);
	return diffs_v[r][p_id[p]]++;
}

int dec_diffs(int r, int p) {
	return diffs_v[r][p_id[p]]--;
}

void swap_diffs(int a, int b) {
	diffs_k[a].swap(diffs_k[b]);
	diffs_v[a].swap(diffs_v[b]);
}

void clear_diffs(int a) {
	for (int x : diffs_k[a]) {
		diffs_v[a][p_id[x]] = 0;
	}
	diffs_k[a].clear();
}

int allsize = 0;

int res_tr[MAXN];
int res_pt = 0;

void increase_res_val(int x) {
	res_tr[x]--;
	res_tr[x+1]++;
	
	res_pt = max(res_pt, x+1);
}

void decrease_res_val(int x) {
	res_tr[x]--;
	res_tr[x-1]++;
	
	if (res_pt == x && res_tr[x] == 0)
		res_pt--;
}

void print_res() {
	if (allsize == 0)
		printf("%d\n", 0);
	else
		printf("%d\n", res_pt+1);
}

void factor(int x) {
	if (x < 2)
		return;
	
	if (prf[x].empty()) {
		int a = x;
		while (a > 1) {
			int d = prime[a];
			if (d == 0)
				d = a;
			prf[x].push_back(d);
			while (a%d == 0)
				a = a/d;
		}
	}
}

void delete_repr(int x) {
	int l = is_repr[x]-1;
	for (auto p : diffs_k[l]) {
		res_tr[diffs_v[l][p_id[p]]]--;
		diffs_v[l][p_id[p]] = 0;
	}
// 	for (auto p : diffs_k[l]) {
// 		res_tr[p]--;
// 	}
	while (true) {
		if (res_pt == 0 || res_tr[res_pt] != 0)
			break;
		res_pt--;
	}
	clear_diffs(l);
	
	if (repr.back() != x) {
		is_repr[repr.back()] = l+1;
		swap(repr[l], repr[repr.size()-1]);
		swap_diffs(l, repr.size()-1);
	}
	
	is_repr[x] = 0;
	repr.pop_back();
}

void add_repr(int a) {
	repr.push_back(a);
	is_repr[a] = repr.size();
	clear_diffs(is_repr[a]-1);
	
	for (int x : repr) {
		int d = abs(x-a);
		factor(d);
		for (int p : prf[d]) {
// 			int nd = diffs[is_repr[a]-1][p]++;
			int nd = inc_diffs(is_repr[a]-1, p);
			increase_res_val(nd);
		}
	}
	
	for (int x : unused) {
		int d = abs(x-a);
		factor(d);
		for (int p : prf[d]) {
// 			int nd = diffs[is_repr[a]-1][p]++;
			int nd = inc_diffs(is_repr[a]-1, p);
			increase_res_val(nd);
		}
	}
}

int main() {
	srand(time(0));
	
	int n, q;
	scanf("%d%d", &n, &q);
	
	for (lli i=2; i<max(n+3, 100); i++) {
// 		factor(i);  // TODO remove if too slow
		if (prime[i] != 0)
			continue;
		
		primes.push_back(i);
		p_id[i] = primes.size() - 1;
		
		for (lli j=2; i*j<=n; j++) {
			prime[i*j] = i;
		}
	}
// 	fprintf(stderr, "initialized\n");
	
	for (int i=0; i<D; i++)
		diffs_v[i].resize(primes.size()+5); // change
	
// 	for (int i=0; i<q; i++) {
// // 		factor(i);
// 		printf("%d: ", i);
// 		for (int a : prf[i])
// 			printf(" %d", a);
// 		printf("\n");
// 	}
// 	return 0;
	
	for (int i=0; i<q; i++) {
		int a;
		scanf("%d", &a);
		
// 		printf("repr: ");
// 		for (int x : repr)
// 			printf(" %d", x);
// 		printf("\n");
// 		for (int j=1; j<=n; j++)
// 			printf("%d ", is_repr[j]);
// 		printf("\n");
// 		printf("unused: ");
// 		for (int x : unused)
// 			printf(" %d", x);
// 		printf("\n");
// 		for (int j=1; j<=n; j++)
// 			printf("%d ", unused_loc[j]);
// 		printf("\n\n");
// 		
// 		printf("(%d)", res_pt);
// 		for (int j=0; j<30; j++)
// 			printf(" %d", res_tr[j]);
// 		printf("\n");
// 		
// 		for (int j=0; j<D; j++) {
// 			for (auto it : diffs[j])
// 				printf(" (%d %d)", it.first, it.second);
// 			printf("\n");
// 		}
// 		printf("\n");
// 		printf(" %d -> %d (%d, %d)\n", i, diffs[19][499], a, repr.size() >= 20 ? repr[19] : -1);
// 		printf("%d\n", a);
// 		for (int j=0; j<D; j++) {
// 			if (diffs[j].find(499) != diffs[j].end()) {
// 				printf("  %d (%d) -> %d\n", j, repr[j], diffs[j][499]);
// 			}
// 		}
		
		if (used[a]) {
			used[a] = 0;
// 			int mock_add = -1;
			
			if (is_repr[a]) {
				// remove from representants list
				delete_repr(a);
				// replace with a new unused if possible
				if (unused.size() > 0) {
// 					printf("replace\n");
					int l = rand()%unused.size();
					int b = unused[l];
					unused_loc[b] = 0;
					
					if (b != unused.back()) {
// 						printf("back\n");
						unused[l] = unused.back();
						unused_loc[unused.back()] = l+1;
					}
					
					unused.pop_back();
					
					add_repr(b);
					// include differences with a
					
					int bd = abs(b-a);
					factor(bd);
					for (int p : prf[bd]) {
// 						int nd = diffs[is_repr[b]-1][p]++;
						int nd = inc_diffs(is_repr[b]-1, p);
						increase_res_val(nd);
					}
				}
			}
			else {
				// is unused
				int loc = unused_loc[a] - 1;
				unused_loc[a] = 0;
				
				if (unused.back() == a) {
					unused.pop_back();
				}
				else {
					int b = unused.back();
					swap(unused[loc], unused[unused.size()-1]);
					unused_loc[b] = loc+1;
					unused.pop_back();
				}
			}
			
			// remove from all diffs
			for (int ri=0; ri < (int)repr.size(); ri++) {
				int d = abs(repr[ri]-a);
// 				printf("R %d %d %d\n", ri, repr[ri], d); // R 19 1513 998 (499); a=515
				factor(d);
				for (int p : prf[d]) {
// 					int nd = diffs[ri][p]--;
					int nd = dec_diffs(ri, p);
// 					printf("  %d %d\n", p, nd);
					decrease_res_val(nd);
				}
			}
			
			allsize--;
			print_res();
			continue;
		}
		
		//new
		used[a] = 1;
		
		// add to all diffs;
		for (int ri=0; ri < (int)repr.size(); ri++) {
			int d = abs(repr[ri]-a);
// 			printf("A %d %d %d\n", ri, repr[ri], d);
			factor(d);
			for (int p : prf[d]) {
// 				printf("  %d\n", p);
// 				int nd = diffs[ri][p]++;
				int nd = inc_diffs(ri, p);
				increase_res_val(nd);
			}
		}
		
		int b;
		b = rand()%(allsize+1);
		
		if (allsize > 1000) {
			b = rand()%(5*allsize+1);
		}
		
		if (b < D) {
			// add to representants
			if (repr.size() == D) {
				// replace with b;
				int bv = repr[b];
				delete_repr(bv);
				
				unused.push_back(bv);
				unused_loc[bv] = unused.size();
			}
			
			add_repr(a);
		}
		else {
			unused.push_back(a);
			unused_loc[a] = unused.size();
		}
		
		allsize++;
		print_res();
	}
	
	return 0;
}