how many pairs whose gcd is 1 cf 547c

/* how many pairs whose gcd is 1 */

int arr[MAX],prime[MAX],p,e[MAX];vi v[MAX];ll ans;int exist[MAX];ll res[MAX],pes[MAX];int len,jk;

void sieve(int n){
    double z = sqrt(n);
    for(ll i = 3;i<=z;i+=2){
        if(!arr[i])
        for(ll j = i*i;j<=n;j+=i+i){
            arr[j] = 1;
        }
    }
    prime[p++] = 2;
    for(int i = 3;i<=n;i+=2)if(!arr[i])prime[p++] = i;
}

void pre(){
    for(int i = 0;i<p;i++){
        for(int j = prime[i];j<MAX;j+=prime[i]){
            v[j].pb(prime[i]);
        }
    }
    e[1] = 1;
    for(int i = 2;i<MAX;i++){
        if((int)v[i].size()&1)e[i] = -1;
        else e[i] = 1;
    }
   for(ll i = 2;i<MAX;i++){
        ll x = i*i;
        for(ll j = x;j<MAX;j+=x)e[j] = 0;
    }
}

void Div(int pos,int pk,ll rr = 1){
    if(pos==len){
        ll z = res[rr];
        z = (z*(z-1))/2;
        ans -= (e[rr] *  z);
        res[rr]+=pk;
        z = res[rr];
        z = (z*(z-1))/2;
        ans += (e[rr] * z);
        return ;

    }
    Div(pos+1,pk,rr * v[jk][pos]);
    Div(pos+1,pk,rr);
}


int main()
{
    booster()
    //read("input.txt");
    sieve(MAX);
    pre();

    int n,q;
    cin>>n>>q;
    for(int i = 1;i<=n;i++){
        cin>>arr[i];
    }
    for(int i = 1;i<=q;i++){
        int a;
        cin>>a;
        len = v[arr[a]].size();
        jk = arr[a];
        if(exist[a]){
            Div(0,-1);
        }
        else {
            Div(0,1);
        }
        exist[a] = 1 - exist[a];
        cout<< ans<<endl;
    }



    return 0;
}