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#include <algorithm>
#include <iostream>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <vector>

// #define DEBUG

const int MAXN = 10000000 + 5;
const int MAXQ = 1000000 + 5;
int A[MAXQ];   // Query
int L[MAXQ];   // Limit
int R[MAXQ];   // Removal pointer
int IP[MAXQ];  // Insertion pointer
int I[MAXN];   // Insertion index
std::unordered_set<int> S;

std::vector<int> P;

long make_pair(int x, int y) { return long(x) | (long(y) << 32); }

const int MAXVM = 20000;
std::unordered_map<long, int> M;
std::vector<int> VM[MAXVM];

int& Find(int p, int a) {
  if (p >= MAXVM) return M[make_pair(p, a%p)];
  if (VM[p].empty()) VM[p].resize(p);
  return VM[p][a%p];
}
// const long MAXM = MAXQ*;
// // const long MAXM = 100000007; // 1.6G
// struct MS {
//   int a, b;
//   int v;
//   bool taken;
// } M[MAXM];
// int Msize = 0;

// long iM[MAXM];

// std::multiset<int, std::greater<int>> V;
int V[MAXQ];
int bestV = 0;

const int MAXP = 10000000;  // 10000000 * 2 / 3;
bool nonP[MAXP + 5];
// int dividor[MAXP + 5];

void init(int n) {
  // Eratostenes sieve
  for (int i = 2; i <= n; ++i) {
    if (!nonP[i]) {
      P.push_back(i);
      // dividor[i] = i;
      for (long j = 2 * i; j <= n; j += i) {
        nonP[j] = true;
        // dividor[j] = i;
      }
    }
  }
}

const int MAXT = 1 << 20;

class Range {
 public:
  void set(int i, int v) { V[i + MAXT] = v; }

  void init() {
    for (int i = MAXT - 1; i > 0; --i) V[i] = std::min(V[2 * i], V[2 * i + 1]);
  }

  int query(int a, int b) {
    a += MAXT;
    b += MAXT;
    int result = std::min(V[a], V[b]);
    while ((a >> 1) < (b >> 1)) {
      if (!(a & 1)) result = std::min(result, V[a + 1]);
      if (b & 1) result = std::min(result, V[b - 1]);
      a >>= 1;
      b >>= 1;
    }
    return result;
  }

  int V[2 * MAXT];
} rt;

void add(int a, int i) {
  for (int p : P) {
    if (p > L[i]) break;

    int& v = Find(p, a);
    // int& v = M[make_pair(p, a % p)];
    // int index = find(p, a % p);
    // int& v = M[index].v;

    if (v > 0) V[v]--;
    ++v;
    V[v]++;
    if (v > bestV) bestV = v;
  }
}

void remove(int a, int i) {
  for (int p : P) {
    if (p > L[IP[i]]) break;
    
    int& v = Find(p, a);
    // auto it = M.find(make_pair(p, a % p));
    // int index = find(p, a % p);
    // int& v = M[index].v;
    // int &v = it->second;
    V[v]--;
    if (bestV == v && V[v] == 0) --bestV;
    --v;
    if (v > 0) V[v]++;
    // else M.erase(it);
  }
}

void pre_add(int a) {}
void pre_remove(int a) {}

int SB[20];

int limit(int n, int d) { return (2 * n + d - 1) / d; }

int test_brute(int n) {
  if (S.size() <= 1) return S.size();
  int k = 0;
  for (int a : S) SB[k++] = a;
  if (abs(SB[0] - SB[1]) == 1)
    return 1;
  else
    return 2;
}

int solve(int i, int n) {
  if (S.size() <= 2) return test_brute(n);
  return bestV;
}

int main() {
  std::ios_base::sync_with_stdio(0);

  int q;
  int n;
  std::cin >> n >> q;
  //   init(std::max(n / 10, 1000l));
  // init((n * 2 + 2) / 3);
  init(limit(n, 3));
  //   std::clog << "P.size() = " << P.size() << std::endl;
  for (int i = 0; i < q; ++i) {
    std::cin >> A[i];
    R[i] = q;
    if (S.count(A[i])) {
      R[I[A[i]]] = i;   // R[i] points to removal of the stone
      IP[i] = I[A[i]];  // IP[i] points to insertion of the stone
      // pre_remove(A[i]);
      S.erase(A[i]);
    } else {
      S.insert(A[i]);
      // pre_add(A[i]);
      I[A[i]] = i;
    }
    rt.set(i, S.size());
  }
  rt.init();
  S.clear();
  for (int i = 0; i < q; ++i) {
    L[i] = limit(n, rt.query(i, R[i] - 1));
    if (S.count(A[i])) {
      remove(A[i], i);
      S.erase(A[i]);
    } else {
      S.insert(A[i]);
      add(A[i], i);
    }
    // std::clog << "S:" << Msize  << "(" << Msize/double(49999993) << ")" << std::endl;
    std::cout << solve(i, n) << "\n";
  }
#ifdef DEBUG
  for (int i = 0; i < q; ++i) {
    std::clog << " " << R[i];
  }
  std::clog << std::endl;
  for (int i = 0; i < q; ++i) {
    std::clog << " " << L[i];
  }
  std::clog << std::endl;
#endif
  return 0;
}