mosh e

#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <stack>
#include <set>
#include <map>
#define pii pair <int,int>
#define vec vector
using namespace std;
using ll = long long;
using ld = long double;
using db = double;
void cv(vector <int> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvl(vector <ll> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}


void cvv(vector <vector <int> > &v){
    for (auto x: v) cv(x);
    cout<<"\n";
}

void cvb(vector <bool> v){
    for (bool x: v) cout<<x<<' ';
    cout<<"\n";
}


int main()
{
    ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int t; cin>>t;
	for (int act=0;act<t;++act){
        queue <int> Q;
        stack <int> S;
        bool st=1, qu=1;
        int n; cin>>n;
        for (int i = 0 ;i < n;++i){
                int d;
            string cmd; cin>>cmd>>d;
            if (cmd == "push"){
                Q.push(d);
                S.push(d);
            }
            else{
                if (Q.front() != d){
                    qu=0;
                }
                Q.pop();

                if (S.top() != d){
                    st = 0;
                }
                S.pop();
            }
        }
        if (st && qu){
            cout<<"both\n";
        }else if (st){
            cout<<"stack\n";
        }else if (qu){
            cout<<"queue\n";
        }else cout<<"none\n";
	}
}