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#include <bits/stdc++.h>
using namespace std;
bitset<10000005> a;
int cnt[3165][3165];
int freq[3165][3165];
int freon[3165];
vector<int> ac;
int pos[10000005];
vector<int> minos;
bool syzyf[3165];
void siro(int l)
{
    for(int i=2; i<=l; i++) syzyf[i]=true;
    for(int p=2; p*p<=l; p++)
    {
        if(syzyf[p])
        {
            for(int i=p*p; i<=l; i+=p) syzyf[i]=false;
        }
    }
    for(int p=2; p<=l; p++) if(syzyf[p]) minos.push_back(p);
}
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n,q;
    cin>>n>>q;
    int pierw=sqrt(n);
    if(pierw<2) pierw=2;
    if(pierw>3162) pierw=3162;
    siro(pierw);
    for(int i:minos) {
        freq[i][0]=i;
        freon[i]=0;
    }
    int yep=0;
    for(int i=0; i<q; ++i)
    {
        int x;
        cin>>x;
        bool plus=!a[x];
        a[x]=!a[x];
        if(plus)
        {
            pos[x]=ac.size();
            ac.push_back(x);
            yep++;
        }
        else
        {
            yep--;
            int p=pos[x];
            int last_val=ac.back();
            ac[p]=last_val;
            pos[last_val]=p;
            ac.pop_back();
        }
        int m1=0;
        for(int i:minos)
        {
            int r=x%i;
            int temp=plus?(cnt[i][r]+1):(cnt[i][r]-1);
            freq[i][cnt[i][r]]--;
            cnt[i][r]=temp;
            freq[i][temp]++;
            if(plus&&temp>freon[i])
            {
                freon[i]=temp;
            }
            else if(!plus&&cnt[i][r]+1==freon[i]&&freq[i][freon[i]]==0)
            {
                freon[i]--;
            }
            if(freon[i]>m1) m1=freon[i];
        }
        int ans=m1;
        if(yep>ans)
        {
            int m2=0;
            if(yep>0) m2=1;
            vector<int> ac2=ac;
            sort(ac2.begin(),ac2.end());
            int roz=ac2.size();
            for(int i=0; i<roz; i++)
            {
                for(int j=i+1; j<roz; j++)
                {
                    int diff=ac2[j]-ac2[i];
                    if(diff<=pierw) continue;
                    int len=0,curr=ac2[i];
                    while(curr<=n&&a[curr])
                    {
                        len++;
                        curr+=diff;
                    }
                    curr=ac2[i]-diff;
                    while(curr>=1&&a[curr])
                    {
                        len++;
                        curr-=diff;
                    }
                    if(len>m2) m2=len;
                }
            }
            if(m2>ans) ans=m2;
        }
        cout<<ans<<"\n";
    }
}