#include <bits/stdc++.h>

using namespace std;

#define PII pair<int,int>
#define pb push_back
#define all(x) (x).begin(), (x).end()

using ll = long long;
using ull = unsigned long long;

struct AAA
{	
	string s1;
	char s2;
	string s3;
};

void solve() {
	int n;
	cin >> n;
	map<pair<string, char>, int> mp;
	map<char, int> mp2;
	int mx = -1;
	char ans = 'A';
	vector<AAA> vec(n);
	for (int i = 0; i < n; i ++) {
		cin >> vec[i].s1 >> vec[i].s2 >> vec[i].s3;
		if(vec[i].s3 == "accepted") {
			pair<string, char> z;
			z.first = vec[i].s1;
			z.second = vec[i].s2; 
			mp[z] ++;
			if(mp[z] == 1) {
				mp2[vec[i].s2] ++;
				if(mp2[vec[i].s2] >= mx) {
					if(vec[i].s2 < ans) {
						ans = vec[i].s2;
					}
				}
			}
		}
	}
	cout << ans << '\n';
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	int tt;
	cin >> tt;
	while (tt--) {
		solve();	
	}

	return 0;
}