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#include <bits/stdc++.h>
#define rep(i, p, k) for (int i = (p); i < (k); ++i)
#define all(v) (v).begin(), (v).end()
#define ll long long
#define fi first
#define sc second
#ifndef DEBUG
#define debug(...)
#else
#include "debug.h"
#endif
using namespace std;
const int MM = 1e7 + 13;
int sv[MM];
const int C = 50;

struct RandSet {
  map<int, int> s;
  vector<int> t;
  mt19937 gen{0xbeeeeee};
  void insert(int x) {
    s[x] = (int)t.size();
    t.push_back(x);
  }
  void erase(int x) {
    auto it = s.find(x);
    if (x == t.back()) {
      t.pop_back();
      s.erase(it);
      return;
    }
    auto it2 = s.find(t.back());
    swap(t[it->sc], t.back());
    t.pop_back();
    it2->sc = it->sc;
    s.erase(it);
  }
  int rand() { return t[gen() % t.size()]; }
};

int solve3(int *t) {
  int a = t[0], b = t[1], c = t[2];
  if (b > c)
    swap(b, c);
  if (a > b)
    swap(a, b);
  if (b > c)
    swap(b, c);
  return 2 + (a + c == 2 * b);
}

struct State {
  map<pair<int, int>, int> cnt;
  int tot = 0;
  RandSet rs;
  int pp[2]{};
  int result() {
    if (tot <= 2)
      return tot;
    if (tot == 3) {
      return solve3(rs.t.data());
    }
    int res = max(pp[0], pp[1]);
    for (auto [_, r] : cnt)
      res = max(res, r);
    return res;
  }
  void add(int x) { pp[x % 2]++; }
  void remove(int x) { pp[x % 2]--; }
};

void brut(int n, int q) {
  int pp[2]{};
  vector<int> t(n);
  vector<int> pos;
  vector<int> cnt(n);
  auto recalc = [&]() {
    int res = max(pp[0], pp[1]);
    int tot = pp[0] + pp[1];
    if (tot <= 2)
      return tot;
    if (tot == 3) {
      return solve3(pos.data());
    }
    for (int i = 3; i * (res - 1) < n && res != tot; i++)
      if (sv[i] == i) {
        memset(cnt.data(), 0, i * sizeof(int));
        for (auto x : pos)
          cnt[x % i]++;
        res = max(res, *max_element(cnt.begin(), cnt.begin() + i));
      }
    return res;
  };
  while (q--) {
    int x;
    cin >> x;
    --x;
    if (t[x] ^= 1) {
      pp[x % 2]++;
      pos.push_back(x);
    } else {
      pp[x % 2]--;
      auto it = find(all(pos), x);
      swap(*it, pos.back());
      pos.pop_back();
    }
    cout << recalc() << '\n';
  }
}

int main() {
  cin.tie(0)->sync_with_stdio(0);
  for (int i = 2; i < MM; i++)
    if (!sv[i])
      for (int j = i; j < MM; j += i)
        sv[j] = i;
  int n, q;
  cin >> n >> q;
  if (1LL * n * q <= 1e10) {
    brut(n, q);
    return 0;
  }
  vector<int> t(n);
  State state;
  while (q--) {
    int x;
    cin >> x;
    --x;
    if (t[x] ^= 1) {
      state.add(x);
    } else {
      state.remove(x);
    }
    cout << state.result() << '\n';
  }
}