#include<bits/stdc++.h>
using namespace std;
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t;
    cin >> t;
    while (t--) {
        unordered_map <string, int> mp;//队名
        int k,co[26]={0};
        cin >> k;
        for (int i = 0; i < k; k++) {
            string team, answer;
            char qus;
            cin >> team >> qus >> answer;
            if (answer == "accepted") {
                if (mp[team] >>(qus-'A') &1) continue;

                mp[team]|=1<<(qus-'A');
                co[qus-'A']++;
            }
        }
        int maxx = -1;char maxname;
        for(int i=0;i<26;i++){
            if(maxx<co[i]) {
                maxx=co[i];maxname=i+'A';
            }
        }
       cout<<maxname<<'\n';
    }
    return 0;
}