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#include <cstdio>

#include <vector>
#include <unordered_set>
#include <algorithm>

std::vector<int> sieve(int n) {
    std::vector<bool> is_prime;
    is_prime.resize(n, true);
    if (n > 0) {
        is_prime[0] = false;
        if (n > 1) {
            is_prime[1] = false;
        }
    }

    for (int i = 4; i < n; i += 2) {
        is_prime[i] = false;
    }
    for (int p = 3; p * p < n; p += 2) {
        if (!is_prime[p]) {
            continue;
        }
        for (int i = p * p; i < n; i += p) {
            is_prime[i] = false;
        }
    }

    std::vector<int> ret;
    for (int p = 2; p < n; p++) {
        if (is_prime[p]) {
            ret.push_back(p);
        }
    }

    return ret;
}

int main() {
    int n, q;
    scanf("%d %d", &n, &q);

    // TODO: Do we need this many primes?
    const auto primes = sieve(n + 1);

    std::unordered_set<int> stones;
    std::vector<int> buckets;
    for (int i = 0; i < q; i++) {
        int pos;
        scanf("%d", &pos);
        auto [it, inserted] = stones.insert(pos);
        if (!inserted) {
            stones.erase(it);
        }

        if (stones.empty()) {
            printf("0\n");
            continue;
        }

        int curr_best = 0;
        for (int p : primes) {
            if (!(p * curr_best <= n && curr_best < (int)stones.size())) {
                break;
            }
            if ((int)buckets.size() < p) {
                buckets.resize(p, 0);
            }
            for (int stone : stones) {
                curr_best = std::max(curr_best, ++buckets[stone % p]);
            }
            for (int stone : stones) {
                --buckets[stone % p];
            }
        }

        printf("%d\n", curr_best);
    }

    return 0;
}