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#include <bits/stdc++.h>
using namespace std;

//roziwazanie z https://www.youtube.com/live/jxYu1MGGjBc moze wejdzie na subpunkty ;(

bool plansza[10000009];
int n,q;
bool notprime[10000009];
unordered_set<int> p;
int md[10000009];

void sito() {
    int q = sqrt(n);
    for (int i = 2; i <= q; i++) {
        if (!notprime[i]) {
            for (int j = i + i; j < n; j += i) {
                notprime[j] = true;
            }
        }
    }
}

int sprawdz(int x) {
    for (auto s: p) {
        md[s%x]++;
    }
    int ans = 0;
    for (auto s: p) {
        ans = max(ans, md[s%x]);
        md[s%x] = 0;
    }
    return ans;
}

int solve() {
    int wyn = sprawdz(2);
    int d = p.size();
    for (int i = 3; i<=(2*n/d);i++) {
        if (!notprime[i]) {
            wyn = max(wyn,sprawdz(i));
        }
    }
    return wyn;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    cin >> n >> q;
    sito();
    while (q--) {
        int x;
        cin >> x;
        if (!plansza[x]) {
            p.insert(x);
        }else {
            p.erase(x);
        }
        plansza[x] = !plansza[x];
        if (p.size() == 0) {
            cout << 0 << endl;
            continue;
        }
        cout << solve() << endl;
    }
}