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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
//mt19937 mrand(random_device{}());
const ll mod=1000000007;
//int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
int gcd(int a,int b) { return b?gcd(b,a%b):a;}
// head

const int N=1e7+5;

#define INF 0x3f3f3f3f

template<class T> inline void read(T &x) {
    x=0; int c=getchar(),f=1;
    for (;!isdigit(c);c=getchar()) if (c==45) f=-1;
    for (;isdigit(c);c=getchar()) (x*=10)+=f*(c-'0');
}

int n,q,spf[N],is_active[N],n_sqrt,cnt[N],offset[3500],freq_small[N],freq[N],divs_buff[3000],small_max,large_max,active_list[N],active_idx[N],active_size;

void sieve(int n) {
    rep(i,2,n+1) if (spf[i]==0) for (int j=i;j<=n;j+=i) if (spf[j]==0) spf[j]=i;
}

struct factor { int p,e;}factors[30];
int n_factors;

inline void factorize(int d) {
    n_factors=0;
    while (d>1) {
        int p=spf[d];
        int e=0;
        while (d%p==0) {
            d/=p;
            e++;
        }
        factors[n_factors++]={p,e};
    }
}

void active_add(int a) {
    active_list[active_size]=a;
    active_idx[a]=active_size;
    active_size++;
}

void active_remove(int a) {
    int i=active_idx[a],last=active_list[active_size-1];
    active_list[i]=last;
    active_idx[last]=i;
    active_size--;
}

int compute_max_through(int a) {
    int res=0;
    VI touched;
    rep(i,0,active_size) {
        int b=active_list[i];
        if (b==a) continue;
        int diff=abs(b-a);
        factorize(diff);
        int n_divs=0;
        divs_buff[n_divs++]=1;
        rep(j,0,n_factors) {
            int pw=1,prev_cnt=n_divs;
            rep(k,0,factors[j].e) {
                pw*=factors[j].p;
                rep(l,0,prev_cnt) divs_buff[n_divs++]=pw*divs_buff[l];
            }
        }
        rep(j,0,n_divs) {
            int d=divs_buff[j];
            if (d>n_sqrt) {
                if (freq[d]==0) touched.pb(d);
                freq[d]++;
                res=max(res,freq[d]);
            }
        }
    }
    for (const auto &d:touched) freq[d]=0;
    return res;
}

int calc_large_max() {
    if (active_size<=1) return active_size;
    int res=1;
    rep(i,0,active_size) res=max(res,compute_max_through(active_list[i])+1);
    return res;
}

int main() {
    scanf("%d%d",&n,&q);
    sieve(n);
    n_sqrt=max(2,(int)sqrt((double)n));
    while ((n_sqrt+1)*(n_sqrt+1)<=n) n_sqrt++;
    int total=0;
    rep(d,2,n_sqrt+1) {
        offset[d]=total;
        total+=d;
    }
    int max_chain_large=(n-1)/(n_sqrt+1)+1;
    freq_small[0]=total;
    rep(i,0,q) {
        int a;
        scanf("%d",&a);
        if (is_active[a]) {
            int max_through_large=1;
            bool need_large=(large_max>1)&&(small_max<large_max||small_max<=max_chain_large);
            if (need_large) max_through_large=compute_max_through(a)+1;
            is_active[a]=false;
            active_remove(a);
            rep(d,2,n_sqrt+1) {
                int r=a%d;
                int idx=offset[d]+r;
                int curr_cnt=cnt[idx];
                cnt[idx]=curr_cnt-1;
                freq_small[curr_cnt]--;
                freq_small[curr_cnt-1]++;
            }
            while (small_max>0&&freq_small[small_max]==0) small_max--;
            if (large_max>active_size) large_max=active_size;
            if (need_large&&max_through_large>=large_max) {
                if (active_size<=1) large_max=active_size;
                else large_max=calc_large_max();
            }
        } else {
            int new_large_candidate=1;
            bool need_large=(small_max<max_chain_large);
            if (need_large) new_large_candidate=compute_max_through(a)+1;
            is_active[a]=true;
            active_add(a);
            rep(d,2,n_sqrt+1) {
                int r=a%d;
                int idx=offset[d]+r;
                int curr_cnt=cnt[idx];
                cnt[idx]=curr_cnt+1;
                freq_small[curr_cnt]--;
                freq_small[curr_cnt+1]++;
            }
            while (freq_small[small_max+1]>0) small_max++;
            if (need_large) large_max=max(large_max,new_large_candidate);
        }
        printf("%d\n",max(small_max,large_max));
    }
}