int main() { set s; int q; int a; int y; cin>>q; while(q>0){ cin>>a; if(a==1){ cin>>y;

        s.insert(y);
    }
    else if(a==2){
        cin>>y;
        auto it=s.find(y);
        if(it!=s.end()){
            s.erase(*it);
        }
        else{
            continue;
        }
    }
    else if(a==3){
        cin>>y;
        auto itr=s.find(y);
        if(itr!=s.end()){
            cout<<"Yes"<<endl;
        }
        else{
            cout<<"No"<<endl;
        }

    }
    q--;
}  
return 0;

}