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#include <cstdio>
#include <vector>
#include <cmath>
#include <unordered_set>

#ifdef LOCAL
    #define dbg(...) fprintf(stderr, __VA_ARGS__)
#else
    #define dbg(...)
#endif

using namespace std;

#ifdef LOCAL
    constexpr int MAX_N=100'000;
#else
    constexpr int MAX_N=10'000'000;
#endif


bool is_prime(const int n, const vector<int>& lower_primes) {
    const int sqrt1 = sqrt(n);
    // start with j=2 because we only check 6n-1, 6n+1, which are never divisible by 2 and 3
    for (unsigned long j = 2; j < lower_primes.size(); ++j) {
        if (lower_primes[j] > sqrt1) {
            break;
        }
        if (n % lower_primes[j] == 0) {
            return false;
        }
    }
    return true;
}

vector<int> compute_primes(const int max_n) {
    vector<int> primes;
    primes.push_back(2);
    primes.push_back(3);

    for (int i = 6; i <= max_n; i += 6) {
        int candidate_1 = i - 1;
        if (is_prime(candidate_1, primes)) {
            dbg("found prime %d\n", candidate_1);
            primes.push_back(candidate_1);
        }

        int candidate_2 = i + 1;
        if (is_prime(candidate_2, primes)) {
            dbg("found prime %d\n", candidate_2);
            primes.push_back(candidate_2);
        }
    }

    return primes;
}

vector<int> factorize(int n, vector<int>& primes) {
    dbg("Factorizing %d\n", n);
    vector<int> fact;

    for (const int prime: primes) {
        while (n % prime == 0) {
            fact.push_back(prime);
            n /= prime;
        }
        if (n == 1) break;
    }
    if (n != 1) fact.push_back(n);
    dbg("Found %lu prime factors\n", fact.size());
    return fact;
}

unordered_set<int> kamyki;
int kamyki_modulo[MAX_N];

int score_for_jumpsize(const int k) {
    int max_score = 0;
    for (auto& kamyk: kamyki) {
        const int m = kamyk % k;
        kamyki_modulo[m]++;
        if (kamyki_modulo[m] > max_score) {
            max_score = kamyki_modulo[m];
        }
    }
    // zero the array
    if (static_cast<int>(kamyki.size()) > k) {
        for (int i = 0; i < k; ++i) {
            kamyki_modulo[i] = 0;
        }
    } else {
        for (auto& kamyk: kamyki) {
            const int m = kamyk % k;
            kamyki_modulo[m] = 0;
        }
    }
    return max_score;
}

int get_max_relevant_num(const int n_size, const int min_score) {
    // highest number that can get score min_score on board of size n_size
    return (n_size-1)/(min_score-1);
}

vector<int> primes_to_consider;

int main() {
    vector<int> primes = compute_primes(MAX_N);
    dbg("Found %lu primes, last one one %d\n\n", primes.size(), primes.back());

    int n, p;

    int kamycount = 0;
    int prevscore = 0;

    scanf("%d %d", &n, &p);
    for (int pi = 0; pi < p; ++pi) {
        int newkamyk;
        scanf("%d", &newkamyk);
        if (kamyki.contains(newkamyk)) {
            kamyki.erase(newkamyk);
            kamycount -= 1;
        } else {
            kamyki.insert(newkamyk);
            kamycount += 1;
        }
        if (kamycount < 3) {
            if (kamycount == 2) {
                dbg("Need to check if stones are adjacent...\n");
                vector<int> ks;
                for (auto& kamyk: kamyki) {
                    ks.push_back(kamyk);
                }
                if (ks[0] == ks[1] + 1 || ks[0] == ks[1] - 1) {
                    printf("1\n");
                    prevscore = 1;
                    continue;
                }
            }
            dbg("Small count = trivial answer\n");
            prevscore = kamycount;
            printf("%d\n", kamycount);
            continue;
        }
        // kamycount >= 3
        int min_score = (kamycount + 1) / 2; // when choosing k=2, we get either all odd or all even
        int max_relevant_num = get_max_relevant_num(n, min_score+1); // k higher than that get less than min_score jumps
        dbg("min score = %d\n", min_score);
        dbg("max relevant num = %d\n", max_relevant_num);
        for (unsigned long j = 0; j < primes.size(); ++j) {
            if (primes[j] <= max_relevant_num) {
                const int score = score_for_jumpsize(primes[j]);
                dbg("Score for prime %d: %d\n", primes[j], score);
                if (score == prevscore + 1) {
                    min_score = score;
                    break;
                }
                if (score > min_score) {
                    min_score = score;
                    max_relevant_num = get_max_relevant_num(n, min_score+1);
                }
            } else {
                dbg("Prime %d was too big to attain score of over %d\n", primes[j], min_score);
                break;
            }
        }
        printf("%d\n", min_score);
        prevscore = min_score;
    }

    return 0;
}