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#include <algorithm>
#include <iostream>
#include <unordered_set>
#include <unordered_map>
#include <map>
#include <vector>
using namespace std;

const int N = 10'000'000;
const int Q = 1'000'000;
int primes[664'579 + 1];
bool isPrime[N + 1];
int primeDivisors[N + 1][10];
int primeDivisorsCounts[N + 1];
unordered_map<int, vector<int>> primeToStoneCount;
vector<int> resultCounts(N + 1);
int res{};

//int SMALL_PRIMES = 303;
int SMALL_PRIMES = 800; // 10 sec

int THRESHOLD = 200;
int THRESHOLD_HIST = 1.05 * THRESHOLD;

struct PairHash {
    size_t operator()(const std::pair<int, int> &p) const {
        return std::hash<int>{}(p.first) ^ (std::hash<int>{}(p.second) << 1);
    }
};

int handleSmallStone(
    unordered_map<pair<int, int>, int, PairHash> &primeToStoneCountSmall,
    map<int, int> &resultsCountSmall,
    unordered_set<int> &stones,
    int a
) {
    unordered_set<int> used;
    for (auto s : stones) {
        int dst = abs(s - a);
        if (dst < 2) {
            continue;
        }
        bool adding = stones.contains(a);
        // cerr << "divisors of " << dst << ": ";
        // for (int i = 0; i < primeDivisorsCounts[dst]; i++) {
        //     cerr << primeDivisors[dst][i] << " ";
        // }
        // cerr << "\n";
        for (int i = 0; i < primeDivisorsCounts[dst]; i++) {
            int p = primeDivisors[dst][i];
            if (used.contains(p)) {
                continue;
            }
            used.insert(p);
            int ap = a % p;
            std::pair<int, int> pap = {p, ap};
            if (primeToStoneCountSmall.contains(pap)) {
                --resultsCountSmall[primeToStoneCountSmall[pap]];
                if (resultsCountSmall[primeToStoneCountSmall[pap]] == 0) {
                    resultsCountSmall.erase(primeToStoneCountSmall[pap]);
                }
            }
            if (adding) {
                ++primeToStoneCountSmall[pap];
                if (primeToStoneCountSmall[pap] == 1) {
                    primeToStoneCountSmall[pap] = 2;
                }
                ++resultsCountSmall[primeToStoneCountSmall[pap]];
            } else {
                --primeToStoneCountSmall[pap];
                if (primeToStoneCountSmall[pap] == 1) {
                    primeToStoneCountSmall.erase(pap);
                } else {
                    ++resultsCountSmall[primeToStoneCountSmall[pap]];
                }
            }
        }
        // cerr << "primeToStoneCountSmall\n";
        // for (auto &[p, count] : primeToStoneCountSmall) {
        //     cerr << "(" << p.first << ", " << p.second << "): " << count << " ";
        // }
        // cerr << "\n";
        // cerr << "resultsCountSmall\n";
        // for (auto &[p, count] : resultsCountSmall) {
        //     cerr << "(" << p << ", " << count << ")\n";
        // }
        // cerr << "\n";
    }
    if (resultsCountSmall.empty()) {
        return ssize(stones) < 2 ? ssize(stones) : 1;
    } else {
        return resultsCountSmall.rbegin()->first;
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, q;
    cin >> n >> q;
    fill(isPrime, isPrime + N + 1, true);
    for (int i = 2; i <= N; i++) {
        primeDivisorsCounts[i] = 0;
    }
    for (int i = 2; i <= N; i++) {
        if (!isPrime[i]) {
            continue;
        }
        for (int j = 2 * i; j <= N; j += i) {
            isPrime[j] = false;
            primeDivisors[j][primeDivisorsCounts[j]++] = i;
        }
    }
    for (int i = 2; i <= N; i++) {
        if (isPrime[i]) {
            primeDivisors[i][0] = i;
            primeDivisorsCounts[i] = 1;
        }
    }
    int idx = 0;
    for (int i = 2; i <= N; i++) {
        if (isPrime[i]) {
            primes[idx++] = i;
        }
    }

    unordered_set<int> stones;
    for (int i = 0; i < SMALL_PRIMES; i++) {
        primeToStoneCount[primes[i]].resize(primes[i], 0);
    }

    unordered_map<pair<int, int>, int, PairHash> primeToStoneCountSmall;
    map<int, int> resultsCountSmall;
    bool smallActive = true;
    bool recalculate = false;
    int counter = 0;
    while (q--) {
        ++counter;
        int a;
        cin >> a;
        if (stones.contains(a)) {
            stones.erase(a);
            for (auto &[p, vec] : primeToStoneCount) {
                int ap = a % p;
                int newCount = --resultCounts[vec[ap]];
                if (res == vec[ap] && newCount == 0) {
                    --res;
                }
                --vec[ap];
                ++resultCounts[vec[ap]];
            }
        } else {
            stones.insert(a);
            for (auto &[p, vec] : primeToStoneCount) {
                int ap = a % p;
                --resultCounts[vec[ap]];
                if (vec[ap] == res) {
                    ++res;
                }
                ++vec[ap];
                ++resultCounts[vec[ap]];
            }
        }
        if (ssize(stones) < THRESHOLD) {
            smallActive = true;
        } else if (ssize(stones) >= THRESHOLD_HIST) {
            smallActive = false;
            recalculate = true;
        }

        int smallRes{};
        if (smallActive) {
            if (recalculate) {
                recalculate = false;
                // for (auto s : stones) {
                //     cout << s << " ";
                // }
                // cout << "\n";
                primeToStoneCountSmall.clear();
                resultsCountSmall.clear();
                auto stonesCopy = stones;
                stones.clear();
                for (auto s : stonesCopy) {
                    stones.insert(s);
                    smallRes = handleSmallStone(primeToStoneCountSmall, resultsCountSmall, stones, s);
                }
            } else {
                smallRes = handleSmallStone(primeToStoneCountSmall, resultsCountSmall, stones, a);
            }
            cout << smallRes << "\n";
        } else {
            cout << res << "\n";
        }
        //        cerr << smallRes << " " << res << "\n";
    }
}