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#include <iostream>
#include <vector>
#include <set>
#include <algorithm>

using namespace std;

const int B = 1500; 

int cnt_data[2000000];
int* cnt[B + 2];
int freq[100005];
int A[100005];
int last_que[100005];
int last_chk[100005];

void brut(int n, int q){
    vector<bool>memo(n+1, 0);
    while(q-->0){
        int x; cin >> x;
        memo[x] = !memo[x];
        int maxi = 0;
        for(int k=2; n>=k; k++){
            for(int s=1; k>=s; s++){
                int curr = 0;
                for(int pos = s; n>=pos; pos += k){
                    if(memo[pos]){
                        curr++;
                    }
                }
                if(curr > maxi){
                    maxi = curr;
                }
            }
        }
        cout<<maxi<<'\n';
    }
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n, q;
    cin>>n>>q;
    if(n <= 2000 and q <= 2000){
        brut(n,q);
        return 0;
    }

    int offset = 0;
    for(int i=2; B>=i; i++){
        cnt[i] = cnt_data + offset;
        offset += i;
        freq[0] += i;
    }
    int maxi = 0;
    set<int> memo;

    for(int xd = 1; q>=xd; xd++){
        int x; cin>>x;
        int delta = (A[x] == 0) ? 1 : -1;
        A[x] = (A[x] == 0) ? 1 : 0;
        if(delta == 1) memo.insert(x);
        else memo.erase(x);

        for(int i=2; min(n, B)>=i; i++){
            int r = x % i;
            int c = cnt[i][r];
            freq[c]--;
            c += delta;
            cnt[i][r] = c;
            freq[c]++;
            if(delta == 1 and c > maxi){
                maxi = c;
            }
        }
        
        if(delta == -1){
            while(maxi > 0 and freq[maxi] == 0){
                maxi--;
            }
        }
        int max_l = maxi;
        int limit = n / B + 1;
        if(max_l < limit){
            vector<int>P(memo.begin(), memo.end());
            int S_val = P.size();
            for(int i=0; S_val>i; i++){
                for(int j=i+1; S_val>j; j++){
                    int D = P[j] - P[i];
                    for(int m=1; D>m*B; m++){
                        if(D % m == 0){
                            int K = D / m;
                            if(K <= B) continue;
                            int r = P[i] % K;
                            if(last_que[K] == xd and last_chk[K] == r) continue;
                            last_que[K] = xd;
                            last_chk[K] = r;
                            int start = r;
                            if(start == 0) start += K; 
                            int c = 0;
                            for(int nxt = start; n>=nxt; nxt += K){
                                if(A[nxt]) c++;
                            }
                            if(c > max_l) max_l = c;
                        }
                    }
                }
            }
        }
        cout << max_l << '\n';
    }
}