#include <bits/stdc++.h>
using namespace std;

int main() {
  vector<tuple<int, int, char>> V(3);
  for (int i = 0, a, b; i < 3 && cin >> a >> b; i++) V.at(i) = make_tuple(a, 100 - b, 'A' + i);
  sort(V.rbegin(), V.rend());
  for (int i = 0; i < 3; i++) cout << get<2>(V.at(i)) << "\n";
}