#include <bits/stdc++.h>

using namespace std;

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

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

	vector<tuple<string,int,int> > t(3);

    string s[3]={"A","B","C"};
    for(int i=0;i<3;++i)
    {
        int h,w;
        cin >> h >> w;
        t[i]=make_tuple(s[i],h,w);
    }
    sort(t.begin(),t.end(),[](auto const& lhs, auto const& rhs) {
    return (get<1>(lhs) > std::get<1>(rhs)) || ((get<1>(lhs) == std::get<1>(rhs)) && (get<2>(lhs) < std::get<2>(rhs)));
  });

    for(const auto& it:t)
	   cout << get<0>(it) << "\n";

	return 0;
}