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#include <bits/stdc++.h>
#pragma GCC target ("avx2,fma")
#pragma GCC optimize ("Ofast")
#pragma GCC optimize ("unroll-loops")

#define ll long long
#define ld long double
#define endl '\n'
#define st first
#define nd second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
#define FOR(i,l,r) for(int i=(l);i<=(r);i++)
#define ROF(i,r,l) for(int i=(r);i>=(l);i--)
using namespace std;
int inf=1000000007;
ll infl=1000000000000000007;
const ll mod=1000000007;

#ifdef LOCAL
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

const int N=10000007,Q=1000007;

int mx[N];
bool pr[N];

bool is[N];
int pos[N];

int cnt[300][300];
int a[Q],ans[Q],ile[Q],val[Q],it[Q];

const int K=11;//tyle par losujemy

int px[Q][2*K],rx[Q][2*K],id[Q][2*K];

int last[Q*K*2],sum[Q*K*2],ac[Q*K*2];

pair<ll,int>Z[Q*K*2];

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    mt19937 rng(21376996);
	const vector<int>P=
	{
		2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
		31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
		73, 79, 83, 89, 97, 101, 103, 107, 109, 113,
		127, 131, 137, 139, 149, 151, 157, 163, 167, 173,
		179, 181, 191, 193, 197, 199, 211
	};
    FOR(i,2,N-1)
    {
		if(pr[i]) continue;
		mx[i]=i;
		for(int j=2*i;j<N;j+=i)
		{
			pr[j]=1;
			mx[j]=max(mx[j],i);
		}
	}
	debug(P);
	int tt,n;
	cin>>tt>>n;
	int xx=0,D=0;
	vector<int>act;
	int siz=0;
	FOR(i,1,n) 
	{
		cin>>a[i];
		is[a[i]]^=1;
		if(is[a[i]]) val[i]=1;
		else val[i]=-1;
		if(val[i]==1)
		{
			pos[a[i]]=sz(act);
			act.pb(a[i]);
		}
		else
		{
			if(pos[a[i]]==sz(act)-1) act.pop_back();
			else
			{
				act[pos[a[i]]]=act.back();
				pos[act.back()]=pos[a[i]];
				act.pop_back();
			}
		}
		D+=val[i];
		FOR(j,0,sz(P)-1)
		{
			int t=a[i]%P[j];
			ile[cnt[j][t]]--;
			cnt[j][t]+=val[i];
			ile[cnt[j][t]]++;
			xx=max(xx,cnt[j][t]);
		}
		while(xx>0&&ile[xx]==0) xx--;
		ans[i]=xx;
		//losowanie
		if(D<=5)
		{
			FOR(x,1,D)
			{
				FOR(y,x+1,D)
				{
					int X=act[x-1],Y=act[y-1];
					int w=abs(X-Y);
					while(mx[w]>P.back())
					{
						int k=mx[w];
						//tutaj mamy nowa pare
						px[i][it[i]]=k;
						rx[i][it[i]]=X%k;
						Z[siz++]={(ll)px[i][it[i]]*N+rx[i][it[i]],2*K*i+it[i]};
						it[i]++;
						while(w%k==0) w/=k;
					}
				}	
			}
		}
		else
		{
			FOR(j,1,K)
			{
				int X=uniform_int_distribution<int>(1,D)(rng);
				int Y=X;
				while(Y==X) Y=uniform_int_distribution<int>(1,D)(rng);	
				X=act[X-1],Y=act[Y-1];
				int w=abs(X-Y);
				while(mx[w]>P.back())
				{
					int k=mx[w];
					//tutaj mamy nowa pare
					px[i][it[i]]=k;
					rx[i][it[i]]=X%k;
					Z[siz++]={(ll)px[i][it[i]]*N+rx[i][it[i]],2*K*i+it[i]};
					it[i]++;
					w/=k; while(w%k==0) w/=k;
				}
			}
		}
	}
	//cout<<sz(Z)<<endl;
	sort(Z,Z+siz);
	int cc=0;
	FOR(i,0,siz-1)
	{
		if(i>0&&Z[i].st!=Z[i-1].st) cc++;
		int i1=Z[i].nd/(2*K),i2=Z[i].nd%(2*K);
		id[i1][i2]=cc;
	}
	act.clear();
	D=0;
	FOR(i,1,n)
	{
		if(val[i]==1)
		{
			pos[a[i]]=sz(act);
			act.pb(a[i]);
		}
		else
		{
			if(pos[a[i]]==sz(act)-1) act.pop_back();
			else
			{
				act[pos[a[i]]]=act.back();
				pos[act.back()]=pos[a[i]];
				act.pop_back();
			}
		}
		D+=val[i];
		FOR(j,0,it[i]-1) ac[id[i][j]]++;
		//biore 3 ostatnie 
		FOR(I,i-4,i)
		{
			if(I<=0) continue;
			FOR(j,0,it[I]-1)
			{
				int t=id[I][j];
				if(last[t]<i)
				{
					if(ac[t]>=D/4)
					{
						int p=px[I][j],r=rx[I][j];
						sum[t]=0;
						FOR(l,0,D-1) if(act[l]%p==r) sum[t]++;
						ac[t]=0,last[t]=i;
					}
					else if(ac[t]>=(i-last[t])/4)
					{
						int p=px[I][j],r=rx[I][j];
						FOR(l,last[t]+1,i) if(a[l]%p==r) sum[t]+=val[l];
						ac[t]=0,last[t]=i;
					}
				}
				if(last[t]==i) ans[i]=max(ans[i],sum[t]);
			}
		}
		cout<<ans[i]<<endl;
	}
	
    return 0;
}