#include<bits/stdc++.h>
using namespace std;
const int N = 1000;
int f[N][N];
int ans[N];
int main(){
	int q;
	cin >> q;
	memset(f,-1,sizeof f);
	while(q--){
		int n;
		cin >> n;
		memset(ans,0,sizeof ans);
		for(int i = 1; i <= n; i++)
		{
			string team;char promble;string res;
			cin >> team >> promble >> res;
			int t = 0;
//			cout << team.size() << endl;
			for(int i = 4; i < team.size(); i ++){
				char e = team[i];
				if( e >='a' && e <='z')
					e = e - 'a' + 'A';
				else
					e = e - 'A';
				t = t *10 + team[i] - 'A';
			}
			int p = promble - 'A';
			int r;
			if(res.compare("accepted") == 0)
				r = 1;
			else
				r = 0;
//			cout << t << " " << p << " " << r << endl;
			if(f[t][p] == -1 && r == 1)
			{
				ans[p] ++;
				f[t][p] = r;
			}
//			cout << ans[p] << endl;	
		}
		int max = -2;
		int base = -1;
		for(int i = 0; i < 32; i ++ ){
//			cout << ans[i] <<" ";
			if(ans[i] > max)
			{
				max = ans[i];
				base = i;
			}
		}
		cout << (char)(base + 'A') << endl;
	}
	return 0;
}