#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

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

    sort(v.begin(), v.end());
    for(int i=0; i<3; ++i)
        cout << get<2>(v[i]) << endl;

    return 0;
}