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#include <bits/stdc++.h>
#define N 10000311
#define P 500
#define S 3311

using namespace std;

int n;
int q;
int sqr;
char sieve[N];
int primes[N];
int prime_count;
char is_stone[N];
int stone_pos[N];
unsigned int visited[N];
int bucket[N];
unsigned int visited_count;
int stones[N];
int stones_size;
int small_primes[P];
int small_primes_count;
int cnt[P][S];
unsigned short *rev_cnt[P];
int w[P];

void eratosthenes() {
    for (int i = 2; i <= n; i++) {
        if (!sieve[i]) {
            primes[prime_count++] = i;
        }

        for (int j = 0; j < prime_count; j++) {
            int p = primes[j];
            if (1LL * i * p > n) {
                break;
            }
            sieve[i * p] = true;
            if (i % p == 0) {
                break;
            }
        }
    }
}

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

    cin >> n >> q;

    sqr = max(2, (int)sqrt(n)) * 2 / 3; // yolo

    eratosthenes();

    small_primes_count = 0;
    for (int i = 0; i < prime_count; i++) {
        if (primes[i] <= sqr) {
            small_primes[small_primes_count] = primes[i];
            small_primes_count++;
        } else {
            break;
        }
    }

    for (int i = 0; i < small_primes_count; i++) {
        int p = small_primes[i];
        int size = n / p + 3;
        rev_cnt[i] = new unsigned short[size];
        memset(rev_cnt[i], 0, sizeof(unsigned short) * size);
        rev_cnt[i][0] = (unsigned short)p;
        w[i] = 0;
    }

    for (int i = 1; i <= n; i++) {
        stone_pos[i] = -1;
    }

    visited_count = 1;
    stones_size = 0;

    while (q--) {
        int x;
        int d;
        cin >> x;

        if (!is_stone[x]) {
            is_stone[x] = true;
            stone_pos[x] = stones_size;
            stones[stones_size] = x;
            stones_size++;
            d = 1;
        } else {
            is_stone[x] = false;
            int idx = stone_pos[x];
            int last = stones[stones_size - 1];
            stones[idx] = last;
            stone_pos[last] = idx;
            stones_size--;
            stone_pos[x] = -1;
            d = -1;
        }

        int ans = 0;

        for (int i = 0; i < small_primes_count; i++) {
            int r = x % small_primes[i];
            int *cnt_row = cnt[i];
            unsigned short *rev_row = rev_cnt[i];

            int old_cnt = cnt_row[r];
            rev_row[old_cnt]--;

            int new_cnt = old_cnt + d;
            cnt_row[r] = new_cnt;
            rev_row[new_cnt]++;

            int best = w[i];

            if (new_cnt > best) {
                best = new_cnt;
            } else {
                while (best > 0 && rev_row[best] == 0) {
                    best--;
                }
            }

            w[i] = best;
            if (best > ans) {
                ans = best;
            }
        }

        int lim = (ans == 0 ? n : (n - 1) / ans);
        if (ans >= 2 && lim > (n >> 1)) {
            lim = (n >> 1);
        }

        if (ans == stones_size) {
            cout << ans << "\n";
            continue;
        }

        for (int i = small_primes_count; primes[i] <= lim && ans < stones_size && i < prime_count ; i++) {
            int p = primes[i];
            int cur = 0;
            visited_count++;
            unsigned int mark = visited_count;

            for (int j = 0; j < stones_size; j++) {
                if (cur + (stones_size - j) <= ans) {
                    break;
                }

                int r = stones[j] % p;

                if (visited[r] != mark) {
                    visited[r] = mark;
                    bucket[r] = 1;
                    if (cur == 0) {
                        cur = 1;
                    }
                } else {
                    int val = bucket[r] + 1;
                    bucket[r] = val;
                    if (val > cur) {
                        cur = val;
                    }
                }
            }

            if (cur > ans) {
                ans = cur;
                int candidate = (n - 1) / ans;
                if (candidate < lim) {
                    lim = candidate;
                }
                if (ans >= 2 && lim > (n >> 1)) {
                    lim = (n >> 1);
                }
            }
        }

        cout << ans << "\n";
    }

    return 0;
}