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#include <bits/stdc++.h>

using namespace std;
#define all(a) (a).begin(),(a).end()
#define ll long long
#define pii pair<int,int>
#define pb push_back
#define F first 
#define S second
#define INF (ll)1e18

const int N = (int) 1e7+4;
bool prime[N];
vector<int> primes;
int cnt[N];

void solve(){

    int n,q; cin >> n >> q;
    set<int> pos;
    for (int i = 0; i < q; i++) {
        int x; cin >> x;
        if (pos.count(x)) {
            pos.erase(x);
        } else {
            pos.insert(x);
        }
        int m = pos.size();
        if (m == 0){
            cout << 0 << "\n";
            continue;
        }
        if (m == 1){
            cout << 1 << "\n";
            continue;
        }
        int ans = m/2;
        for (auto j : primes) {
            if (j > (2*n+m-1)/m) break;
            for (auto x : pos)
                ans = max(ans, ++cnt[x%j]);
            for (auto x : pos)
                cnt[x%j] = 0;
        }
        cout << ans << '\n';
    }

}

int32_t main(){

    ios::sync_with_stdio(0);
    cin.tie(0);

    fill(prime, prime + N, true);
    prime[0] = prime[1] = false;
    for (int i = 2; i * i < N; i++) {
        if (prime[i]) {
            primes.push_back(i);
            for (int j = i * i; j < N; j += i) {
                prime[j] = false;
            }
        }
    }

    int t=1;
    //cin >> t;
    while(t--){
        solve();
    }
    return 0;
}