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

int main(){
    tuple<int, int, char> A[3];
    for (int i = 0; i < 3; i++){
        cin >> get<0>(A[i]) >> get<1>(A[i]);
        get<1>(A[i]) *= -1;
        get<2>(A[i]) = 'A'+i;
    }
    sort(A, A+3);
    reverse(A, A+3);

    for (int i = 0; i < 3; i++){
        cout << get<2>(A[i]) << endl;
    }
}